The 120V BRK Electronics wired-in smoke alarm is fast and easy to install. Interconnects up to 12 alarms enabling one unit to trigger all of the alarms, improving safety and security. Features an 85 decibel alarm with an ionization sensor equipped to detect fires before they spread! Designed with a power-on LED indicator light, test/reset button, and a quick disconnect button. Alarms meet UL standard 217. Comes with two locking devices to prevent battery theft. Offers a 10 year limited warranty. Alarm dimensions: 5.6" Dia. x 2.0" H.