Make your life safer – This smoke detector with 3 V lithium battery has photoelectric sensor which is optimized to detect even slow smoldering fires. Alarm also features a loud 85 dB alarm, easy mounting bracket, a single test/silence button, and an end-of-life signal so you know when to replace the battery. For maximum protection and the ultimate in assurance, you can depend on Logilink's smoke detector to secure what matters most in life.