The Kidde Carbon Monoxide Detector with 10-Year Battery & Digital Display, model C3010D, is a carbon monoxide detector that uses electrochemical sensor technology to detect carbon monoxide. The CO detector is powered by a 10-year lithium battery that never needs replacing, plus protects during a power failure. The Kidde alarm is conveniently designed and portable enough for travel - simply install it on a wall or place it on a tabletop. When carbon monoxide is detected, an 85-decibel alarm will sound & a red LED will flash. A green LED indicates that the alarm is receiving power. And an amber LED indicates when it's time to replace the detector. The test-hush button allows you to test the battery operations as well as temporarily silence the low battery chirp warning. Plus, peak level memory records the last time carbon monoxide was detected or when the unit was last tested. Install a smoke detector & carbon monoxide detector on every level of your home and near bedrooms to help keep your family safe from fire & poisonous gas. UL Certified with a 10-year limited manufacturer's warranty.