First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide Alarm with Battery Backup

10 Years CO sensor and alarm life Latching alarm indicator remembers which unit initiated an alarm Superior carbon monoxide sensor and dual ionization smoke alarm|Inter-connectable with BRK and First Alert hardwired smoke and carbon monoxide alarms|Easy to install universal mount bracket|Simple to use silence/test button; separate smoke and CO latching alarm indicators|9-volt battery included; 7-year limited warranty The BRK hardwire combination smoke and carbon monoxide alarm detects two hazards with one simple unit. Carbon monoxide (CO) is a colorless, odorless, deadly gas. It can be emitted by sources including gas or oil furnaces, gas clothes dryers, water heaters, fireplaces, wood stoves, charcoal grills, gas ranges, and space heaters. A clogged chimney, improper venting, and attached garages can also cause carbon monoxide accumulation. According to the Consumer Product Safety Commission (CPSC), at least one CO alarm should be installed near a home's sleeping area. The BRK SC912