Smoke and carbon monoxide alarm displays two oval speaker vents and a Kidde logo, showing its front face with a test/silence button mounted against a plain white background.
This product has been Discontinued

Battery Powered Wireless Smoke & Carbon Monoxide Alarm

KN-COSM-B-RF

The Kidde KN-COSM-B-RF Combination Smoke & Carbon Monoxide Alarm provides two important safety devices in a single unit. This alarm includes a voice warning system that announces “Fire”, “Warning, Carbon Monoxide”, “Low Battery”, and “Caution, Carbon Monoxide Previously Detected.” 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.

  • Wireless Interconnect
    Interconnect without wires – when one alarm sounds they all do.

  • Voice Alarm
    Announces the hazard type detected.

  • Test/Reset Button
    Tests alarm circuitry and triggers the voice announcement.

  • LEDs
    Two LEDs are provided. Flashing green for normal operation and flashing red for alarm condition.

Helpful Resources

Helpful Resources

Click on the video to learn more about how to install your Kidde Smoke and Carbon Monoxide alarm.

Download iconProduct Data Sheet
Download iconUser Guide
Download iconSupport
Thumbnail of the video "Understanding your Fire Alarm Sounds"Play button
A red fire extinguisher and three Kidde smoke/CO detectors (one boxed) stand arranged on a light wood tabletop against a pale wall, accompanied by a round "#1" safety-brand badge.

Why Kidde

As North America's #1 home fire safety brand,* Kidde has been working to help make your home the safest it can be for more than 100 years. Now, our latest smoke alarms and combination smoke + carbon monoxide (CO) alarms are bringing you the next level of fire and CO safety. Help protect what matters most in your life with features like cutting edge technology that send fast alerts to give your family more time to get out safely. And enhanced sensing technology that reduces false alarms often caused by cooking.

*Based on total household installations as of December 2023.