9 V Battery Powered Photoelectric Smoke Alarm with excellent stability and high-sensitivity. 

Key Specifications/Special Features
Power Source: 9 V Battery (included). 
Audio Alarm: & g e; 85 dB /3 m
Temperature Range: 0 to 40 degree
Humidity Range: 5%-95% relative humidity(RH)
Sensor: Photoelectric
Size: 106mm in diameter X32mm depth
Interconnects: No
Easy to install with mounting base included
Suitable for any room
Low battery signal
Test button for simple testing

Pls feel free to contact me for more details, welcome to do business with us!!