... 220VAC power supply,9V back-up battery,85dB/3m,Wireless interconnection,meets EN14604,UL217 Test by hand,Low battery warningHush ... , high stabilityOperating Voltage:120V/220V ACBackup Battery: 9V battery Static current: ≤10uA Alarm current: ≤15mA Alarm indication: LED flash Sound level: ≥ ... 06%/ft Detecting area: 20 square meters Alarm output: sound and flash alarm Size: 128 x 38mm deep Wireless ...