This Kidde carbon monoxide alarm is designed to provide a loud, 85-decibel warning before the level of tasteless, odorless carbon monoxide in your home becomes dangerous. Its sensitive, electrochemical sensor detects from anywhere in the room. Its test/silencer button allows you to check electronic functions or quiet the alarm while you locate the source of trouble. Battery operation provides protection during power outages. Snap-open cover gives you easy access to batteries. Uses 3 AA batteries (included). 5-yr. limited manufacturer's warranty. No. KN-COB-B. Imported. ~5-1/4Lx5-1/4Wx1-1/4D"