120V Hardwire, Photo Smoke w/9V battery backup

? Optipath 360 Technology ? Patented Photoelectric smoke sensing design
? 9V battery back-up ? Easy access battery door
? Two Latching features ? Alarm latch and Low battery latch
? Two Silence Features ? Silence low battery chirp for up to eight hours or temporarily silence nuisance alarm conditions
? Low battery warning
? 10-Year Limited Warranty