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  • DEFENDER 21031 SENTINEL 8-Channel Smart Security DVR with 8 Ultra Resolution Outdoor Security Cameras
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DEFENDER 21031 SENTINEL 8-Channel Smart Security DVR with 8 Ultra Resolution Outdoor Security Cameras

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Price: $479.99 and eligible for FREE Two-Day Shipping Details
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21031 8-Channel, 8-Camera
  • Choose motion-activated recording or H.264 compression to maximize storage space
  • Super resolution cameras provide crisp and detailed video
  • Monitor up to 100 feet away in complete darkness with automatic night vision
  • View anytime, anywhere with remote viewing via internet, smartphone, and tablet
18 used from $389.99

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Frequently Bought Together

DEFENDER 21031 SENTINEL 8-Channel Smart Security DVR with 8 Ultra Resolution Outdoor Security Cameras + VideoSecu 4 Pack 150 Feet Video Power CCTV Security Camera Cables with BNC to RCA Adapter Connector 1OA + BNC Female to Female Coupler Adapters Pack of 10
Price for all three: $536.44

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Style: 21031 8-Channel, 8-Camera
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Technical Details

Style: 21031 8-Channel, 8-Camera
  • DC in Jack
  • Mouse Included

Product Details

Style Name: 21031 8-Channel, 8-Camera
  • Product Dimensions: 20.7 x 11.4 x 14.2 inches ; 11 pounds
  • Shipping Weight: 24.5 pounds (View shipping rates and policies)
  • Shipping: This item is also available for shipping to select countries outside the U.S.
  • ASIN: B007ULT4K4
  • Item model number: 21031
  • Average Customer Review: 3.6 out of 5 stars  See all reviews (221 customer reviews)
  • Amazon Best Sellers Rank:
  • Date first available at Amazon.com: May 1, 2012

Product Description

Style: 21031 8-Channel, 8-Camera

From the Manufacturer

Trust DEFENDER® to make thieves and vandals think twice about approaching your property. DEFENDER® systems function just like a computer, with a mouse for pointing and clicking and an intuitive icon-based menu for easy set up and use. View anytime, anywhere with remote viewing via internet, smartphone, and tablet and receive email alerts, with photo, when motion is detected on your property. Record over 2 years' worth of footage on the included 500GB hard drive. Eight all-weather cameras deliver clear, ultra hi-res video with 600 TVL for maximum surveillance indoors and outdoors. 36IR LEDs allow for 100ft of automatic night vision. Anti-vandal mount ensures cameras cannot be tampered with and 65ft of cable allows for greater flexibility in mounting around your home or business. Don't give thieves a chance. Stop them with DEFENDER®! Item has different model numbers:Model# is 21031 but it consists of 1 DVR with Model# 21013 and 8 Cameras with Modle# 21006.

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Extremely easy to set up and use

This DEFENDER® system functions just like a computer, with a mouse for pointing and clicking and an intuitive icon-based menu that provides prompts and coaching to assist you in navigating the system. It’s even so simple to use it will begin recording as soon as it’s plugged in.

View your camera footage from anywhere in the world

Whether monitoring your business or home, view your footage live online, anytime and anywhere with PC or Mac. You can also view footage on almost any smartphone, including iPhone®, BlackBerry®, Android™, Windows Mobile®, or Symbian™, as well as on your iPad® and most major tablets.

Instant email alerts if activity detected

Instantly know if suspicious activity is happening on your property. This DEFENDER® system is designed to send you an email alert, complete with photo, if any motion is detected on your property or if any of your cameras experience video loss.
Crisp and detailed video | View Larger

IR Cut filter for crisp and detailed video you can rely on

Your security system is only worthwhile if you can actually see the person stealing from you. DEFENDER® cameras are equipped with 600 TV lines of resolution and an IR cut filter to enhance color and detail. The DVR records in D1 resolution, which is the equivalent of 704 x 480 pixels or DVD quality. The result is clear, crisp and accurate video feed.

Two years’ worth of footage storage – and more if you need it

The included 500 GB hard drive allows continuous monitoring and recording of over two years’ worth of footage! Your DVR sends an alert when your memory space is full so that you can choose to overwrite old video or stop the unit from recording. The built-in USB port gives you the option of backing up and transferring your video footage with a USB flash drive or external USB hard drive. And if you need to expand your storage even further, you can choose to record only when motion is detected. This DVR uses H.264 compression which maximizes recording time, transfers data more efficiently over the internet and you’ll use 50% less storage space than traditional compressions - MPEG4, MJPEG - while still benefitting from high-quality imagery.
100ft night vision | View Larger

When everyone else is asleep, our cameras are watching closely

The things that go bump in the night are sometimes a thief making off with your big-screen TV. DEFENDER® cameras are equipped with night vision that automatically activates. Thirty-six infrared ClearVu® LEDs provide crisp and detailed night imagery as you monitor from up to 100ft away, even in complete darkness. So thieves may think they’re lurking in the dark but you can rest assured DEFENDER® will see them.

Weather resistant | View Larger

Rain or Snow won’t stop us

Criminals don’t take the night off if it’s raining. Neither do our cameras. They’re weather resistant and ensure optimal picture quality no matter what Mother Nature decides to throw at you, be it rain, hail or snow. The professional-grade aluminum housing, complete with sunshade, will protect against rust, deterioration and glare. So no matter what’s going on outside, DEFENDER® will be ready

Vandal resistant mount | View Larger

Secure wiring can’t be tampered with

Thieves know dismantling a security system is a good way to get off scot free. But they’ll be disappointed with DEFENDER®. Each camera’s 65ft of cable runs through the cable mount and then directly into the wall, leaving no part of the cable exposed. Your footage will be secure.

See more with 8 cameras

Thieves don’t limit themselves to just a few rooms. Neither should your security system. Monitor up to 8 areas with this 8CH DEFENDER® DVR kit. By adding all included cameras you’ll be able to keep an eye on your entire property, enjoying even greater peace of mind.

Lifetime Live Customer Support

Our customer support team can be reached by phone or by email and live web chat. You’ll always have access to an expert. Support is available in English, Spanish and French.

Product Description

Record over 2 years' worth of footage on the included 500 GB hard drive

Customer Questions & Answers

Customer Reviews

Very easy install and works great.
Amazon Customer
Just when I started to think I got what I paid for I was disappointed when two of the cameras was not working properly.
The cameras capture a very clear picture and the night vision is excellent.

Most Helpful Customer Reviews

260 of 268 people found the following review helpful By R. Precourt on August 11, 2012
Style Name: 4-Channel, 4-Camera Verified Purchase
I've been on the fence about buying one of these systems for a little over a year now and finally decided on this one.

My needs were:

* 4 outdoor cameras
* Good resolution
* Good night vision
* DVR with network capability
* Ability to view cameras from multiple computers and smartphone
* Price range of $300-$350

This system appeared to meet all my needs and I had noticed over the past year that the Defender systems seemed to have the best overall ratings. I further researched the on-line manual for this system (as I frequently do for things that I'm serious about purchasing) and it also gave me comfort that the system would meet my needs.

I've had the system installed for about a week now and I am quite pleased with it. That being said, I would like to share my overall experience with everyone, as it may be helpful for those considering this system and installing it themselves, as I did.

I did a few things backwards, but found it helpful in adjusting the cameras once I had everything wired.

First off, the entire system was packaged very nicely - great presentation and well organized. All of the camera cables were rolled up nicely on plastic spools. All parts were neatly arranged and well labeled.

Next, I took everything out of the box and hooked up to my 40" Samsung LCD via VGA cable to test it out. Note: the manual indicates that if you hook the DVR up using VGA to an LCD TV or monitor that the mouse and remote will not function. I called Defender to inquire about this prior to purchasing and they informed me that the unit WILL work fine via VGA and they were correct.
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342 of 358 people found the following review helpful By Wayne TOP 1000 REVIEWER on July 10, 2012
Style Name: 21031 8-Channel, 8-Camera Vine Customer Review of Free Product ( What's this? )
A few years ago I installed a PC-based security system similar to this from Q-See in our old house. It was quite a bit more complicated than this all-in-one setup as it involved setting up PC-based Hardware, buggy software, and 13 different types of indoor and outdoor cameras.

At the moment, I haven't permanently installed the camera's yet, as they are temporarily placed inside and outside of the house in various locations as I evaluate the system and determine the best placement. So let's walk through the system so you hopefully have a better idea of what you're getting into, and how it performs.


There are 3 separate boxes, in a bigger box. One has the DVR itself and associated material. And the other 2 larger boxes include all of the camera hardware and wires. The wires for the cameras are 65' and combine both the BNC (for video) and DC power connector into one cable. This should make running wires much easier.

The end of the cable that goes to your DVR will connect the BNC cable to the DVR, and then the DC power cable connects to a 4-way DC->AC adapter. This is much prefered to the older designs where each camera had it's own bulky transformer to plug into.

There is mounting hardware for the cameras, which is rather basic. You'll want to check this out and make sure it's suitable for what and where you are going to mount these cameras into. You definitely don't want them falling down. I'll get more into Installation later.

They've also included an RJ45 network cable, RCA cable, Quick Start Guide, and a small USB mouse. The USB mouse is small and cheap, but you can use any USB mouse you have laying around. If you want more instructions, you can use the included mini-CD which has a full PDF users guide.
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531 of 604 people found the following review helpful By Joe Goldade on January 5, 2013
Style Name: 21031 8-Channel, 8-Camera Verified Purchase
The system and cameras work very well (except the screws for the camera mounts rust almost instantly upon contact with water, as noted in other reviews.)

I'm an I.T. professional, and I'd like to expose a HUGE security flaw with this system. This defender system (along with other models this company makes: Q-See, NightOwl, SVAT, etc.) has two major problems:

1) It has an open telnet port with a root username. For my own security, I'm not going to list the password here, but it took me less than 4 days to crack it brute force. This is inexcusable. I even wrote the company asking them to close this port for me, and they refused, and treated me with disrespect. (Read the response I received below.)

2) Anyone can login to the web portal using ANY username you choose with the pwd 519070. Isn't scary to know that you could essentially find the login page for anyone's DVR, enter foobar for the username, and 519070 as the password and, viola! You're in! Be forewarned, I had to write software to restrict access to this DVR login page (rerouting DNS entry lookups, a custom ACL list, and restricted MAC address access on my router.)

I was also interested in writing a custom piece of software to use on my android phone (just like the software aSee), so I wrote the company the following letter requesting information - their response not only didn't help, it pissed me off. Here's the complete email trail.

Good afternoon,

I'm hoping to be able to get some information from you about the Defender DVR system Model 21031 I purchased.

I noticed that aSee is a supported application that allows streaming from this DVR on port 18004. But how does this work?
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