10-Year lithium power cells provide continuous power to alarm for at least 10 years Tamperproof housing prevents unauthorized deactivation of the alarm or removal of the battery* Loud 85dB audible alarm * Single button tests alarm function and silences alarm in event of false alarm * Meets UL217 standard and code for sealed/tamperproof alarms * Ideal for high ceilings, apartments, rental property, dorm rooms and hallways * 10-year limited warranty * Model# SA340CN