Smoke alarm, 9V, sounder, wireless interconnect SND-500-SW

Photoelectric smoke sensing chamber technology Integrated indicator provides visual indication of both the quiescent condition and an alarm condition Test and Hush functions in a single button Test button verifies battery and alarm operation Test and Hush visual indicator Loud 85 dB sounder to alert occupants Surface-mount device (SMD) circuit board design Single DC 9 V user-replaceable battery provides up to 18 months operation under normal conditions 30-day low battery audible warning signal Battery missing indicator prevents the unit from being installed without the battery fitted Up to 38 units interconnectable using the wired transmission path