Sealed-In lithium battery.| Maintenance and hassle-free with prevention from tampering and removal.| The alarm is always on, with no battery replacement required for the 10-year life-span of the alarm| Photoelectric sensor advanced sensor to detect visible particles associated with smouldering fires| Intelligent multi-sensor alarm - detects both smoke and carbon monoxide| Single screw-mounting bracket - enables quick and easy installation. The alarm is automatically activated once installed| Smart Hush™ button - temporarily silences nuisance and false alarms| Test/Reset button - tests the alarm circuitry and horn. Resets memory after the alarm has sounded| End-of-life signal - chirps every 30-45 seconds to signal that alarm needs to be replaced| Deactivation switch - disables the alarm to allow for safe battery disposal once the unit has reached the end of its 10-year life. The tamper-resistant feature prevents a disabled alarm from being placed back onto the mounting bracket| 10-year limited warranty - provides peace-of-mind with a decade of smoke and fire detection| Complies with Australian Standard AS 3786:2014 incl. Amdt 1 and Activfire listed for quality assurance.