Operating principle: Photoelectric Alarm current: < 50mA, Quiescent current: 85 dB/3m, Battery life: 3 years. Wifi module: Power: 3V Replaceable battery (2 pcs 1.5V AA Battery) Quiescent current: <8uA Alarm current: Operating principle: Photoelectric Alarm current:< 50mA, Quiescent current: 85 dB/3m, Battery life: 3 years. Wifi module: Power: 3V Replaceable battery (2 pcs 1.5V AA Battery) Quiescent current: <8uA Alarm current: < 50mA, Quiescent current: 85 dB/3m, Battery life: 3 years. Wifi module: Power: 3V Replaceable battery (2 pcs 1.5V AA Battery) Quiescent current: <8uA Alarm current: < 50mA, Quiescent current: 85 dB/3m, Battery life: 3 years. Wifi module: Power: 3V Replaceable battery (2 pcs 1.5V AA Battery) Quiescent current: <8uA Alarm current: <80mA. Frequency: 2.4 GHz.