Detection Method: Photoelectric Power: 240V Backup: 9V Battery, 1 year life Alarm sound: 85 dB at 3m minimum Low battery indication: Visual LED (red) for warning & low battery Operating Distance: N/A indoor use line of sight; 140m free field Temperature: 0 ā 45C Humidity: 5 ā 95% Dimensions:Ā 140mm x 55mm Maximum number of devices: 40 pieces for wired alarm Warranty:Ā 10 Years Compliance: AS 3786: 2014/amdt 2:2018