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Mighty Mule FM231 Wireless Driveway Alarm – Electromagnetic Vehicle Detection, Indoor Receiver, 400 ft Range, Expandable, Battery Powered, Easy Installation, Driveway & Property Security System

4.2 out of 5 stars 4,175 ratings
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Purchase options and add-ons

Brand Mighty Mule
Color Multicolor
Power Source cordless-electric
Compatible Devices Compatible with Mighty Mule
Item dimensions L x W x H 6 x 3 x 13 inches

About this item

  • Electromagnetic Vehicle Detection: Detects vehicles using an electromagnetic sensor system, ensuring reliable notifications when vehicles enter or exit your property
  • Indoor Receiver with Audible Chime: The included receiver emits a chime when a vehicle is detected, promptly alerting you of any driveway activity
  • Up to 400 ft Wireless Range: Offers a wireless range from the transmitter to the receiver of up to 400 ft, providing security coverage for large properties
  • Easy Installation & Battery Powered: Simple to install by burying the sensor next to your driveway; powered by 2 AA batteries (not included) with a low battery indicator
  • Expandable System: Add multiple indoor receivers (sold separately) for broader coverage across different areas of your property
  • Mighty Mule driveway alarm, has been a trusted choice by customers for over 20 years. Additional base station can be purchased separately (FRM231-R)

Frequently bought together

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Product information

Technical Details

Brand ‎Mighty Mule
Color ‎Multicolor
Power Source ‎cordless-electric
Compatible Devices ‎Compatible with Mighty Mule
Item dimensions L x W x H ‎6 x 3 x 13 inches
Connectivity Technology ‎Wireless
Installation Type ‎Wireless DIY
Alert Type ‎Motion
Item Weight ‎1.5 Pounds
Control Method ‎Touch
Maximum Range ‎12 Feet
Included Components ‎Transmitter, Sensor, Receiver, Transformer, Mounting Post, Instruction Manual
Noise Level ‎125 dB
Unit Count ‎1.0 Count
Global Trade Identification Number ‎00090835001501, 00090835001488
UPC ‎723521743095 094713465348 728639291933 763500157772 090835001488 090835001600 090835001501 791043564047
Manufacturer ‎Mighty Mule
Part Number ‎FM231
Item Weight ‎1.5 pounds
Product Dimensions ‎6 x 3 x 13 inches
Country of Origin ‎China
Item model number ‎FM231
Is Discontinued By Manufacturer ‎No
Size ‎Pack of 1
Style ‎Security System
Finish ‎Multicolor
Material ‎Plastic
Item Package Quantity ‎1
Batteries Included? ‎No
Batteries Required? ‎Yes
Warranty Description ‎Limited 12 Month Manufacturers Warranty (from date of purchase)

Additional Information

ASIN B003765W0W
Customer Reviews
4.2 out of 5 stars 4,175 ratings

4.2 out of 5 stars
Best Sellers Rank #92 in Home Security Systems
Date First Available September 25, 2008

Warranty & Support

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Product Warranty: For warranty information about this product, please click here [PDF ]

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Mighty Mule FM231 Wireless Driveway Alarm – Electromagnetic Vehicle Detection, Indoor Receiver, 400 ft Range, Expandable, Battery Powered, Easy Installation, Driveway & Property Security System


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Product Description

Product Description

The Mighty Mule FM231 Wireless Driveway Alarm provides reliable vehicle detection to help secure your home, business, or property. Unlike traditional motion sensors, the FM231 uses an electromagnetic sensor system to detect the movement of large metal objects like cars, ensuring fewer false alarms caused by animals or pedestrians. Once a vehicle is detected, the sensor sends a signal to the indoor receiver, which alerts you with an audible chime. This driveway alarm offers a wireless range of up to 400 feet between the outdoor transmitter and the indoor receiver, making it suitable for monitoring larger properties or long driveways. The system is expandable, allowing you to add additional indoor receivers in different areas, ensuring you never miss an alert. The sensor is easy to install by burying it next to your driveway, and the battery-powered transmitter means no complicated wiring is necessary. The system operates on 2 AA batteries (not included) and features a low battery indicator for both the sensor and the receiver to prevent downtime. Designed to perform reliably in most outdoor conditions, the FM231 offers a durable and weather-resistant setup, although care should be taken to protect the transmitter from direct exposure to sprinklers or heavy rain. Whether you're securing a home, business, or rural property, the Mighty Mule FM231 provides an efficient, cost-effective solution for vehicle detection and driveway security.

From the Manufacturer

Keep track of vehicles entering or exiting your property with the Mighty Mule Driveway Alarm. (FM131) When a vehicle passes the sensor, the receiver emits an audible tone. Easy to Install and stake is included in kit. The electromagnetic sensor will sense large metal objects and send a signal to the interior base station to let you know someone is there. Install the batteries, near the installation site so the sensor can "learn" the area. If the batteries are installed in the home; the unit may not function properly.

Top Brand: Mighty Mule

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Customer reviews

4.2 out of 5 stars
4,175 global ratings

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Customers say

Customers find the driveway alarm works well and is easy to install following instructions, considering it a good investment for property security. The detection ability is positive, with every vehicle entering the driveway being detected, and customers consider it worth the price. The alarm quality, reliability, and range receive mixed feedback - while some say it rarely gives false alarms and is well-built, others report issues with false alarms and unreliability within months. The loudness and range also get mixed reviews, with some finding the sound loud enough while others want it louder, and while some say the signal travels far, others note the wireless range is limited.

1,269 customers mention "Works well"976 positive293 negative

Customers find that the driveway alarm works well, with one customer noting it functions effectively through brick walls and another mentioning it operates in every room of their house.

"...It works perfectly and every time now. I can't say for sure what fixed it other than the different location must transmit better...." Read more

"8 month review. This is an exceptional unit. Battery life on 2 AA batteries is unexpectedly long, even in winter...." Read more

"...The 1st alarm worked very well so everything went into the ground...." Read more

"...Update: May 10, 2017 - To date, it has performed exceptionally well with zero false alarms and zero failures to sound off at the appropriate time...." Read more

371 customers mention "Ease of installation"341 positive30 negative

Customers find the driveway alarm easy to install following the instructions, with one customer noting it's simple to pair with the receiver and another mentioning it's straightforward to attach to any antenna.

"This is an excellent product. It has mostly clear and accurate instructions...." Read more

"...LIKES: Distance the signal transmits to the house. Ease of installation. DISLIKE: Length of the USB cable from sensor to the transmitter...." Read more

"Installed properly according to instructions. I have full view of my driveway, neighbor's driveways on both sides, and the road...." Read more

"...Then, easy enough to attach to any antenna via RF coax (with SMA connectors). On the transmitter, the addition was a little trickier...." Read more

220 customers mention "Value for money"178 positive42 negative

Customers find the driveway alarm to be worth the price, considering it a good investment for property security.

"...Amazon price is a good value , batteries last about 1.5 - 2 years." Read more

"...I like that it uses two AA batteries, cheap and plentiful. The inside unit is strictly powered by the AC adapter. No batteries...." Read more

"...We are impressed so far, great for the price...." Read more

"...But this one is quite affordable and meets our needs...." Read more

176 customers mention "Detection ability"132 positive44 negative

Customers appreciate the driveway alarm's detection ability, noting that it effectively detects every vehicle entering the driveway, with one customer mentioning it works well with metal on wheels.

"...So far the Mighty Mule has detected every vehicle that has gone past it and not one false alarm...." Read more

"...off when a vehicle (this can include a riding lawn mower) trips it - no birds, squirrels, deer, dogs!!..." Read more

"I highly recommend this "Driveway Monitor." It detects the metal in a car, truck, mower, etc...." Read more

"...It senses someone driving down the driveway (doesn't sense the deer), sends the signal to the receiver and the receiver "chirps" three times...." Read more

540 customers mention "Alarm quality"356 positive184 negative

Customers have mixed experiences with the security system's alarm: while some report it rarely gives false alarms, others mention it fails to go off sometimes.

"...The batteries last for several years. It rarely gives a false alarm. If it beeps and the light is green you best check your driveway...." Read more

"...May 10, 2017 - To date, it has performed exceptionally well with zero false alarms and zero failures to sound off at the appropriate time...." Read more

"...And it there are sporadic false alarms, try changing the codes. Some have reported trouble in rain...." Read more

"...Ultimately it’s a nice alert so I can go out and deal with deliveries and such but the people who talk about it for security...." Read more

240 customers mention "Reliability"94 positive146 negative

Customers have mixed experiences with the security system's reliability, with some finding it well-built and amazing considering its quality, while others report that it becomes unreliable within months and deteriorates over time.

"...It's inexpensive, and that inevitably means less than perfect quality control, so install promptly." Read more

"...moles as we do here this will save you a problem later on and pvc pipe is very cheep and available at any hardware store or home center...." Read more

"This product works pretty well for a driveway alarm. They don’t last forever!..." Read more

"...I also like the activity light on the monitoring unit. The entire unit is built well and has survived well so far...." Read more

223 customers mention "Loudness"96 positive127 negative

Customers have mixed opinions about the security system's alarm sound: while some find it loud enough and appreciate the audible signal, others note that the base volume is low and that it randomly sounds when nothing is present.

"...I only gave it 4 stars because the chime on the receiver is too soft...." Read more

"...The alarm is loud enough to be heard throughout the house. It will send a new signal with each car (after about 15 seconds between)...." Read more

"...Regular AA batteries last 3 months. The alarm went off LOUDLY in middle of night to alert us to low battery. I unplugged it and it kept beeping!..." Read more

"...The alarm volume is plenty loud. Later in the day, it detected the UPS truck going in and out...." Read more

205 customers mention "Range"121 positive84 negative

Customers have mixed experiences with the security system's range, with some reporting it travels up to 250 feet while others find it limited.

"...This told me that the transmission was good, but there was something hindering the signal from the sensor to the transmitter...." Read more

"I like it and the way it works just wish the range was greater" Read more

"...It is line of sight, the transmitter is up high, and there is likely no other interference...." Read more

"...This one had pretty good reviews and was supposed to have a range out to 400 ft. I installed it and never could get it to work...." Read more

Best Sensor for Metal Objects
5 out of 5 stars
Best Sensor for Metal Objects
I've tried motion detection driveway alarms, but they are too sensitive to birds, leaves, bugs and maybe wind. I could never determine what triggered the motion alarms each time, but there were many false alarms. This is my second Mighty Mule. No, they don't last forever; mine worked great for 6 years. Averaging about $12 per year, this sensor is a bargain. Like my first one, only vehicles that come and go trigger this new detector. I presume and expect it will give me years of service, as did the first one.
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Top reviews from the United States

  • Reviewed in the United States on April 30, 2025
    Replaced a Mighty Mule driveway alert system that was at end of life. System works in -20 degree F below zero to 100 degree F temperatures. Amazon price is a good value , batteries last about 1.5 - 2 years.
  • Reviewed in the United States on December 30, 2013
    I have been using this for about 3 weeks now and very happy with it. It was a replacement for an older Infrared alarm that stopped working. I have had 2 of the infrared alarms over the years and they never did work very well. They would alarm several times a day from birds, small animals, deer, even nearby branches blowing in the wind. Sometimes, vehicles coming down the drive would not be detected. So far the Mighty Mule has detected every vehicle that has gone past it and not one false alarm. Now if you need an alarm to notify you when a person enters your driveway then this may not work for you as it senses the change in the magnetic field as a vehicle passes. I live out in the country and the closest neighbor is over 1/4 mile away. If there is another drive way next to yours you may need to experiment with different locations to find one that works. My driveway is over 200 Ft. long so that makes the distance from the transmitter to the receiver over 200 FT. So far that has not been a problem. I did mount the receiver close to a window because we have metal siding that blocks all kinds of wireless signals. So if you live in a mobile home that is something to consider. Also there is some labor involved in installing it. The instructions say to bury the sensor 12 inches deep and as close to the driveway as possible. I only went down about 8 inches and mounted the transmitter about 6 Ft. back from the driveway. I also ran the cable in 3/4 pvc pipe to protect it. If you have moles as we do here this will save you a problem later on and pvc pipe is very cheep and available at any hardware store or home center. I purchased a 10 ft. length for less than $2.00. I would suggest that you dig a hole deep enough to position the sensor pipe without trying to hammer it in the ground. You may damage the cable. I used a 3/4 "sweep L" that is also available in the electrical section of any home center to make the bend from the horizontal to the vertical pipe. I know this sounds like a lot of trouble but it really isn't. If you have a shovel that is all you need. A posthole digger is nice but not necessary. The cable is rated for direct burial so you don't need to glue the pvc pipe. I would highly recommend this unit to anyone who needs to know when someone is coming down your driveway.

    Update 4/29/24 I purchased this in December of 2013. I still have it and it still works just fine. The batteries last for several years. It rarely gives a false alarm. If it beeps and the light is green you best check your driveway. This is without question the best driveway alert you will find anywhere.
    .
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  • Reviewed in the United States on February 24, 2016
    This is an excellent product. It has mostly clear and accurate instructions.

    However, let me give a more detailed description of my experience. My drive is long and in the front of our house. All our windows are toward the back, so we could never tell when someone was coming without standing at a window waiting. So, the idea of a remote sensor was very appealing. I read the reviews for this product and it seemed as though concerns about range were that it would work well for my needs. However, I didn't want this 1' tall pipe with the transmitter standing in the middle of the yard. I was hoping to find a longer cord from the sensor to the transmitter so I could hide it by a tree at about 30'. I called customer support for the company to see if this was possible and found out that the cable that connects them is a simple computer USB cable...they suggested that I could add a longer extension cable to make it possible to hide the transmitter farther away from the drive (the cable is only about 10' long). So, I ordered the unit and bought some extra 6' long USB extension cables. When the unit came, I had a beautiful mid-winter 60 degree day and went out to dig my trench for the unit. Since I was burying the USB with junctions, I bagged the connections in plastic and used heavy tape to keep water out. When I completed the task, the unit worked GREAT! Total success. However, the next morning, it didn't work! Why? I never could really figure it out. The connections were all snug and dry, but the transmitter only worked intermittently. VERY frustrating. I called the company again. They said that perhaps the batteries were not able to handle the cold (it was no longer 60 degrees and was below freezing over night.) So, I went out and bought lithium batteries....no difference. Not only was it intermittent, but the frequency of success seemed to diminish.

    I read the manual again and found that it says "Do not splice the cable". I concluded that this meant I should not use the USB extension cables, even though the tech told me I could do this. So, I took out the extensions and put the pole the 10' from the driveway (ugly). But it worked for a day, then seemed to stop again...back to intermittent success. Back to tech support....they advised "resetting" the unit...taking the battery out for 30 seconds, then reinserting to let it recalibrate. I did this a number of times...every time I reinserted the battery, the alarm would go off inside. This told me that the transmission was good, but there was something hindering the signal from the sensor to the transmitter.

    I was ready to give up and called the tech support again. He told me that they had done all they could do to help me over the phone and they gave me a return authorization. He told me that I should be sure it didn't work because if they got it back and it worked for them, they would just send it back to me. (I was not really happy at this point...) However, I decided I would remove the item....as I brought it back into the house with the batteries still inserted, it set off the alarm whenever I walked past something with even a little metal in it. Hmmmm...this told me that it WAS properly sensing and transmitting and that perhaps my line of sight in my original location was not as good as I thought. I reburied the unit in a different location that is farther away from the house and not as obvious that the pole is sticking out of the ground...it actually has a superior line of sight to the house and ... VOILA! It works perfectly and every time now. I can't say for sure what fixed it other than the different location must transmit better.

    So, this was very frustrating to get it set up. 1) You need to be sure you can avoid splicing the USB and have a transmission spot 10' from the driveway. 2) You do need lithium batteries. 3) Be sure you have excellent line of sight from the transmitter to the receiver location in the house (it does not need to be through a window, however)...I may have had zebra grass blowing about 1/2 way between my original location...don't know. 4) The alarm is loud enough to be heard throughout the house. It will send a new signal with each car (after about 15 seconds between). 5) Once it is working, DON'T TOUCH IT! (I really don't know if it would affect it, but I am not taking any chances. My rating is 4* because of the trials and frustration getting it to work. As for the way it works, it is great and worthy of 5*. It works just as advertised finally and we can now await our visitors sitting in the back of the house without seeing the driveway. Good product.
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Top reviews from other countries

  • Fraulein
    5.0 out of 5 stars Working great, no more false alarms. Should have bought it long ago.
    Reviewed in Canada on September 10, 2019
    Edit after 4.5 years.
    I am still very please with this unit. It's been running flawlessly for the last 4.5 years. Like I said earlier, I had to place the sensor unit at about 20 feet away from the main road. Because there is a lot of heavy traffic and sometime I got a false alarm because a heavily loaded semi truck went by. My driveway is about 100 feet long.
    Today after 4.5 years of continuous use, I had my first low battery warning. I use the brand name alkaline batteries. So the batteries last a very long time. I am sure my unit is still working fine in part because it is protected by an big PVC pipe (see pictures).
    --------------------------------
    Edit after 18 months.
    I am still very pleased with this unit. I am still running the same batteries since I installed it 18 months ago. The cold weather of winter does not seems to bother it at all. Even after been totally covered in snow it is still working fine. As you can see in my picture my apparatus is well protected with a big plastic pipe with very good venting. I believe this is important so humidity does not saturate the equipment.
    --------------------------------------------
    Great driveway alarm. Works great. No more false alarm. Before this one I had one of those wire less motion detector drive way alarm. About the third of the price of this one. But there were always false alarms. Animals (deer, cat, etc), branches moving in the wind and when the clouds keeps on hiding the sun intermittently, this was causing false alarms.

    Now with this one no more problems. Every time the alarm sound, there is a car in my driveway. I installed it about 30 feet from the road. I live on a very busy road, it is a road that lead to the US border, so there is always many cars and heavy trucks that go by. I happened to have a piece of 3 inches ABS tube with an elbow so I ran the device in the tube. I also happened to have a 4 inches PVC pipe. So I made a sleeve that slide perfectly over the ABS pipe. I just added a cover and put some holes (pointing downward) so there will be a good aeration and the rain will not enter. This way the access is very easy for maintenance and changing the batteries. I also painted it with some camouflage paint. Next summer, the grass will growth around the pipe and will help to hide it.

    The receptor does not sound very loud nor for very long. If you happen to sneeze while the alarm goes off, you will miss it. However there is a light that come ON and remain ON (until you reset it), to tell you the device have been triggered. Also it is possible to buy more receptors. I bought an extra one. Now I have one in my living / dinning room and another downstairs in the basement.

    Very handy, now I can be in my workshop in the basement without missing the delivery truck that brings me my Amazon parcels. Before that, I always hesitated to move far from my kitchen window when I expect a parcel. This is very liberating.
    Customer image
    Fraulein
    5.0 out of 5 stars
    Working great, no more false alarms. Should have bought it long ago.

    Reviewed in Canada on September 10, 2019
    Edit after 4.5 years.
    I am still very please with this unit. It's been running flawlessly for the last 4.5 years. Like I said earlier, I had to place the sensor unit at about 20 feet away from the main road. Because there is a lot of heavy traffic and sometime I got a false alarm because a heavily loaded semi truck went by. My driveway is about 100 feet long.
    Today after 4.5 years of continuous use, I had my first low battery warning. I use the brand name alkaline batteries. So the batteries last a very long time. I am sure my unit is still working fine in part because it is protected by an big PVC pipe (see pictures).
    --------------------------------
    Edit after 18 months.
    I am still very pleased with this unit. I am still running the same batteries since I installed it 18 months ago. The cold weather of winter does not seems to bother it at all. Even after been totally covered in snow it is still working fine. As you can see in my picture my apparatus is well protected with a big plastic pipe with very good venting. I believe this is important so humidity does not saturate the equipment.
    --------------------------------------------
    Great driveway alarm. Works great. No more false alarm. Before this one I had one of those wire less motion detector drive way alarm. About the third of the price of this one. But there were always false alarms. Animals (deer, cat, etc), branches moving in the wind and when the clouds keeps on hiding the sun intermittently, this was causing false alarms.

    Now with this one no more problems. Every time the alarm sound, there is a car in my driveway. I installed it about 30 feet from the road. I live on a very busy road, it is a road that lead to the US border, so there is always many cars and heavy trucks that go by. I happened to have a piece of 3 inches ABS tube with an elbow so I ran the device in the tube. I also happened to have a 4 inches PVC pipe. So I made a sleeve that slide perfectly over the ABS pipe. I just added a cover and put some holes (pointing downward) so there will be a good aeration and the rain will not enter. This way the access is very easy for maintenance and changing the batteries. I also painted it with some camouflage paint. Next summer, the grass will growth around the pipe and will help to hide it.

    The receptor does not sound very loud nor for very long. If you happen to sneeze while the alarm goes off, you will miss it. However there is a light that come ON and remain ON (until you reset it), to tell you the device have been triggered. Also it is possible to buy more receptors. I bought an extra one. Now I have one in my living / dinning room and another downstairs in the basement.

    Very handy, now I can be in my workshop in the basement without missing the delivery truck that brings me my Amazon parcels. Before that, I always hesitated to move far from my kitchen window when I expect a parcel. This is very liberating.
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  • Mark L-S
    5.0 out of 5 stars Right Technology, Right Product
    Reviewed in Canada on November 21, 2013
    I have taken several months before writing a review on this product, since I have had problems with other metal sensor driveway alarms in the past. In principle the technology is wonderful. We live in the country off a fairly busy County Road with our house screened by trees about 75 feet from the roadway. A motion detector does not work in this application because of animals, heavy trucks passing and various other "ghost" positives. We then tried two other makes of metal sensor alarm with mixed results. When they worked they were clearly the right technology for our application, but they ate batteries that were hard to replace, became infested with ants (the sensors were mounted on a tree) and they also gave off false positives from tree motion and especially when the batteries were low. In addition they seemed to be orphans from the start. We were on our own making them work. So, right technology, poor product - which is obviously why they are no longer on the market! Even with their flaws we found a driveway alarm to be very valuable to alert us to vehicles entering our driveway in our rural situation.
    After scouring the market for other metal sensing alarms for over a year, I finally took the plunge and tried the Mighty Mule FM231 with some skepticism. After 4 or 5 months of use, I can say it is exactly what were were looking for. It uses a sensor that is buried in the lawn beside the driveway (rather than pole or tree mounted). It takes AA batteries that are easily accessible and economical to replace ( I haven't yet had to replace them). It has a sensitivity control that can be adjusted to screen out everything but passing vehicles. My experience wasn't entirely problem free. The transformer unit used to power the house alarm which came in the kit was defective, but even this turned out to be a positive experience. I had no trouble contacting a knowledgeable technical support person at the Florida headquarters of Mighty Mule and he arranged for a replacement transformer to be couriered to me at the manufacturers expense with no fuss or hassle. That is comforting!
    I should caution other potential buyer that I cannot comment directly on the effective range of the wireless signal from the transmitter to the house since we have a short driveway and the transmitter is less than 20 feet from the receiver in the house, but I have moved the receiver around a bit within the house and there seems to be no problem with fading signals through the triple brick walls. I would have reasonable confidence that it would work over substantially greater distances. So my conclusion is right technology, right product. I hope this helps.
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  • Andrew Robin
    4.0 out of 5 stars Better than motion detector
    Reviewed in Canada on December 17, 2021
    I purchased this in the winter so currently have the sensor laying on top of the ground parallel to the driveway. It is under about 2 feet of snow and the distance from the driveway sensor to the receiver in the house is 150' and so far it has been working perfectly.

    This is replacing a motion detector and has been much superior in every aspect. No false alarms due to animals or weather conditions.

    I like the green "visitor" light that goes on after the alarm is activated and remains lit until you push the reset button on receiver in the house. This lets you know if someone has been down the driveway while you are not home or do not happen to hear the alarm.

    The cord could certainly be a little longer to allow the transmitter to be located further from the driveway sensor. Some posts have indicated they have added a USB cable to extend the length of the cord provided. This connection would of course be underground so proper precautions would have to be taken to ensure this connection is not affected by moisture. I cannot comment if this would have any negative impact on the overall performance of the driveway alarm.

    Overall, I have been very pleased with this so far and will bury the sensor and cable in the spring.
  • Lisa Mallett
    1.0 out of 5 stars I have had three now. All three stop working. Not recommended.
    Reviewed in Canada on March 3, 2020
    UPDATE: I recommend purchasers may want to stay away from this product unless they have tenacity and patience.
    My first Mighty Mule did not work for more than one week, so I immediately returned it for a new one.
    Amazon was great and sent a replacement one to me right away.
    I installed the second one and it also did not work, worse than the first actually. I lost interest in it and just started to investigate returning it to Mighty Mule today as I have tinkered with it over the last number of months to no avail.
    I have now been on hold for an hour trying to find out how to return it I have been shunted from dept to dept and no one seems to know what to do because I bought through Amazon.
    So a long story short... you may be on your own if you buy one of these. They work poorly...I have had two.
    They also seem to have poor product support and certainly no place to send an email inquiry....your only hope is to hang on the phone for quite possibly hours. Which I did.
    I was about to give up...and planned to write off my hundred dollar investment as a bad one.
    But...lo and behold, Finally I got through.
    The last gentleman I spoke to, Gregory, at Mighty Mule was very nice, helpful and I will be getting a replacement...hopefully third times a charm.
    NOPE: third one worked for about two years, stop working last spring….replaced batteries, dug it up and reinstalled….nothing fixed it. So disappointed.
  • Amazon Customer
    5.0 out of 5 stars Works great with no false alarms
    Reviewed in Canada on January 9, 2025
    Does exactly as described. Only issue is transmitter needs a good line of sight with receiver (no concrete or grade barriers)