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Kidde 21026043 Battery-Operated(Not Hardwired) Combination Smoke/Carbon Monoxide Alarm with Voice Warning KN-COSM-BA

by Kidde
4.6 out of 5 stars 5,908 ratings
Amazon's Choice recommends highly rated and well-priced products.
Amazon's Choice for "kidde smoke and carbon monoxide alarm"

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  • Voice alarm –Announces the hazard type detected thereby helping to speed up the correct reaction to the hazard detected. Alarm announces “Fire” when a smoke or fire hazard is detected and announces “Warning Carbon Monoxide” when a CO hazard is detected
  • Combined carbon monoxide and smoke alarm – A single unit can be installed where previously, two were needed. Reduces installation time and helps to keep home décor attractive.
  • Audio alarm: 85 dB at 10 feet. Test/Reset Button and LEDs – Tests alarm circuitry and triggers the voice announcement. Flashing green for normal operation and flashing red for alarm condition. Humidity Range: 10 percent to 95 percent relative humidity non-condensing
  • Battery - Provides protection even during power outages when many fire and carbon monoxide incidents occur. The unit warns of a low battery condition by announcing “low battery” and by initiating an alarm chirp and activating a flashing red LED. The battery door will not close unless the batteries are properly installed. Note: The date printed on the item is manufacturing date, not the expiration date. Refer to the PDF attached below in technical specification for manual.
  • Voice announcements - Hush Feature temporarily silences nuisance alarms with “Hush Mode Activated” and “Hush Mode Cancelled” voice announcement. If the alarm had detected a CO level of 100ppm or higher, the unit will announce “Carbon Monoxide Previously Detected” to warn of the CO incident, when the test/ reset button is pressed. Temperature range: 40˚F (4.4˚C) to 100˚F (37.8˚C). Voltage (volts):4.5
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Kidde 21026043 Battery-Operated(Not Hardwired) Combination Smoke/Carbon Monoxide Alarm with Voice Warning KN-COSM-BA
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Customer Rating 4.6 out of 5 stars (5908) 4.6 out of 5 stars (3499) 4.6 out of 5 stars (7020) 4.3 out of 5 stars (733) 4.6 out of 5 stars (4200) 4.7 out of 5 stars (7017)
Price $24.88 $33.93 $34.85 $34.50 $35.99 $28.03
Shipping FREE Shipping on your first order. Details FREE Shipping. Details FREE Shipping. Details FREE Shipping. Details FREE Shipping. Details FREE Shipping. Details
Sold By Amazon.com Amazon.com Amazon.com DealsOnWings Amazon.com Amazon.com
Color White White White White White White
Item Dimensions 1.80 x 5.60 x 5.60 inches 2.00 x 6.00 x 6.00 inches 2.00 x 5.00 x 5.00 inches 5.22 x 5.22 x 1.60 inches 5.60 x 5.60 x 1.90 inches 6.06 x 3.75 x 1.75 inches

Product description

Size:1 Pack

Kidde 21026043 Battery-Operated (Not Hardwired) Combination Smoke/Carbon Monoxide Alarm with Voice Warning KN-COSM-BA. Interconnects - No.


Product information

Size:1 Pack

Technical Details

Technical Specification

Other Content [PDF ]
User Guide [PDF ]
User Manual [PDF ]
Warranty [PDF ]

Additional Information

Warranty & Support

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

Customer Questions & Answers

Customer reviews

4.6 out of 5 stars
4.6 out of 5
5,908 customer ratings
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Reviewed in the United States on November 6, 2017
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Myk K.
3.0 out of 5 stars Price
Reviewed in Canada on February 21, 2020
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