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

Limit 3 per customer


The Kidde KN-COSM-BA battery-operated carbon monoxide and smoke alarm combines two important safety devices into a single unit.

This alarm includes a voice warning system that makes four announcements: fire, carbon monoxide, low battery, or smart hush activation. The voice alarm eliminates any confusion and clearly warns you and your family of a smoke or carbon monoxide danger, or if your battery is in need of replacement. This unit uses AA batteries, protecting you and your family even during a power outage. This alarm uses ionization-sensing technology for the smoke alarm. Ionization-sensing alarms may detect invisible fire particles (associated with flaming fires) sooner than photoelectric alarms. Photoelectric-sensing alarms may detect visible particles (associated with smoldering fires) sooner than ionization alarms. Kidde strongly recommends that both ionization and photoelectric smoke alarms be installed to help ensure maximum detection of the various types of fire that can occur within the home.

For additional peace of mind, the alarm also contains a test/reset button that enables you to periodically test its circuitry and horn. If any form of battery failure is detected, the red LED light will flash and the unit will chirp one time, followed by the warning message, "low battery." This cycle will occur once every minute, and will continue for at least seven days. Seven years after initial power up, this unit will chirp" every 30 seconds.

This is an operational end-of-life feature that will indicate that it is time to replace the alarm. UL 2034, the independent standard applicable to CO alarms, requires CO alarms to have an end-of-life warning. This requirement went into effect in March 2007, meaning any CO alarm manufactured after April 2007 with a UL listing must have this feature. Most states that require CO alarms in residential dwellings mandate that the alarm meet the UL 2034 standard.

Alarm Warnings Fire:

The red LED will flash and be accompanied by three long alarm beeps followed by a verbal warning message: "Fire! Fire!" The alarm will repeat the pattern until smoke is eliminated.

Carbon Monoxide:

Four short alarm beeps followed by a verbal warning: "Warning--carbon monoxide!" This continues until the unit is reset or the CO is eliminated.

Low Battery:

One chirp followed by warning: "Low battery." The red LED light will flash. This pattern will continue every minute for the first hour. After the first hour, the red LED light will flash once every minute and will be accompanied by the chirp sound. The low-battery warning will only sound once every 15 minutes.

Voice Hush Indication:

"Hush activated" and "Hush canceled" voice announcement. Peak Level Memory: If the alarm had detected a CO level of 100ppm or higher when the test/reset button is pressed, the unit will announce, "Carbon monoxide previously detected" to warn of the CO incident. Trademarked Hush Feature for Convenience By pressing the hush button, you can easily and safely silence nuisance alarms caused by non-emergency situations, such as overcooked dinners. This feature desensitizes the alarm for approximately 10 minutes. If the smoke is not too dense, the alarm will silence immediately, the unit will verbally announce, "Hush mode activated," and the green LED will flash every two seconds for approximately 10 minutes.

  • Smart 2-in-1 Voice Alarm - Voice announces "Fire!" or "Warning! Carbon Monoxide"
  • Smart Hush - Nuisance alarms are silenced by pressing the hush button.
  • Battery Safeguard with Front Load Battery Door - Quick and easy battery replacement.
  • Test/Reset Button, LEDs, and Low Battery Warning. Temperature Range: 40˚F (4.4˚C) to 100˚F (37.8˚C)
  • Meets Underwriters Laboratories (UL) UL2034 and UL217 compliance.

Shipping Note: Shipping to Alaska, Hawaii, and PO Boxes is not available for this item

Warranty: 90 Day Woot Limited Warranty


In the box:

  • (1) Kidde KN-COSM-BA Battery-Operated (Not Hardwired) Combination Smoke/Carbon Monoxide Alarm with Voice Warning
  • (2) AA Batteries
  • (1) User Manual


In the box:

  • (1) Kidde KN-COSM-BA Battery-Operated (Not Hardwired) Combination Smoke/Carbon Monoxide Alarm with Voice Warning
  • (2) AA Batteries
  • (1) User Manual

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Kidde Battery-Power Smoke/Carbon Monoxide Alarm
$19.99 Sold Out Home & Garden
$19.99 USD false 1 Retail EA
1 3
Woot! Sellout.Woot
4121 International Pkwy Carollton TX 75007 U.S.A.