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Kidde Hardwired Smoke and Carbon Monoxide Detector with Battery Backup and Voice Alarm KN-COSM-IBA

The Kidde Hardwired Smoke and Carbon Monoxide Detector with Battery Backup and Voice Alarm KN-COSM-IBA uses breakthrough technology to offer a fast response to real fires, including smoldering and fast-flaming, as well as protect you from carbon monoxide and dramatically reduce the chance of nuisance alarms. The Intelligent sensor technology combines the detection capabilities of an ionization smoke sensor – which is more likely to detect smaller, less visible fire particles, like those produced by flaming fires – with that of an electrochemical sensor, which is used to detect CO. Since carbon monoxide is present in all fires, having both detection chambers work together in one alarm is a breakthrough in the fire safety industry. When either sensor notices a potential hazard, it will communicate with the other. Depending on what is detected, the alarm will adjust its smoke sensitivity in order to better discriminate between a real hazard and a false one. This constant communication enhances the alarm’s overall performance in all fires, and significantly reduces the potential for a nuisance alarm. Connect up to 24 (18 initiating alarms) for devices, when one device is activated all connected alarms activate throughout the home.

Complete with an adjustable mounting bracket, mounting hardware, a quick-connecting wire harness, two AA batteries and a user’s manual, this smoke and carbon monoxide alarm is easily set up in any room of your home for instant protection. It has a battery safeguard so it can’t accidentally be mounted without batteries. It meets the safety standards set by Underwriters Laboratories (UL) so that you can be confident of its quality.

Leading authorities recommend that both ionization and photoelectric smoke alarms be installed to help ensure maximum detection of the various types of fires that can occur within the home. Ionization sensing alarms may detect invisible fire particles (associated with fast flaming fires) sooner than photoelectric alarms. Photoelectric sensing alarms may detect visible fire particles (associated with slow smoldering fires) sooner than ionization alarms.


  • Talking alarm announces the hazard type detected, helping to speed up reaction time
  • Employs both smoke and carbon monoxide sensors
  • Inter-connectable to provide improved protection
  • Features a hush button to silence the alarm for non-emergency situations like a smoky dinner
  • Battery safeguard ensures the unit cannot be accidentally mounted without batteries


  • Model: KN-COSM-IBA
  • Part Number: 21026041
  • Power Source: 120VAC, 60Hz 45mA max per alarm 2 AA battery backup
  • SmokeSensor: Ionization
  • CoSensor: Electrochemical
  • Audio Alarm: 85dB at 10ft
  • Temperature Range: 40˚F (4.4˚C) to 100˚F (37.8˚C)
  • Humidity Range: 10%-95% relative humidity, non-condensing
  • Size: 5.6” in diameter x 1.8” depth
  • Weight: 1 lb.
  • Wiring: Quick connect plug with 6” pigtails
  • Interconnects: Up to 24 Kidde devices (of which 18 can be initiating)
  • U.S. Shipping

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  • Global Shipping

    We can ship to your customers worldwide. Shipping fees for international orders are automatically calculated at checkout and is based on the destination, shipping class and product