Kidde Hardwired Smoke Detector With 10-Year Battery Backup, Interconnectable & LED Warning Lights, model 20SA10. This smoke detector has enhanced sensing technology that reduces false alarms often caused by cooking and sends fast alerts that help give your family more time to get out safely. Plus, it is interconnected so when one alarm sounds, they all do so you never miss an emergency (see user guide for compatibility With other Kidde models). This alarm offers a modern 5-inch design ideal for all living spaces such as living rooms, hallways, kitchens, & bedrooms. Comprehensively tested and designed to the latest UL standard for safety and reliability, the 5-inch smoke alarm is powered by 120V AC wiring With a 10-year built-in lithium battery, so you never have to change a battery for the life of the detector (not a battery performance claim). When smoke is detected, the red LED light will flash in time With the loud 85-decibel alarm to help you seek safety. A test-hush button allows you to test the battery operations as well as silence nuisance alarms, should they occur. In addition, the detector is self-testing and easy to install With the included twist-and-click mounting bracket. Meets requirements of 9th Edition UL 217, FCC, and CSFM.