First Alert 0827B 10-Year Sealed-Battery Ionization Smoke Alarm

• Complies with all current 10-year legislation in states/cities where required;• Ionization sensor provides earliest possible warning of a fast-flaming fire; optimized for fires such as those caused by paper, kitchen grease, and other fast-combusting materials;• Loud 85 dB alarm;• Mute button silences unnecessary alarms; also tests alarm's function;• Easy installation with twist and mount hardware;• Tamperproof, sealed alarm design provides constant protection for alarm's life;• 10-year limited warranty;• Includes 3-volt lithium power cell; no battery changes for expected life of alarm ;• Round;