FireAngel Safety Technology FS2126-T Smoke Alarm Multi Sensor with Sleep Easy 85dB 10 Year Battery Smart RF Ready- Product: Smoke Alarm- Type: 10 Year- Rated Supply Voltage: 3 V- Power Supply Mains: 3 V- Wiring Method: Battery Operated- Voltage Type: DC- Detection Type: Multi-Sensor- Maximum number of detectors: 50- Battery Life Span: 10- c/w Batteries: Y