1.Test manually，auto reset. 2.Use in dependence. 3.Two-face glass fiber circuit board,stainless steel shield. 4.ASIC adopted,Dustproof,mothproof,anti-light interference design. 5.Strong adaptability to circumstance. 6.SMT manufacture technology,high stability. 7.Operating voltage:DC9-16V battery,Static current: 3mA;alarm current:25mA.3.Alarm output:Relay output/sound&flash alarm. 8.Alarm volume: more than 85dB/3 meters. 9.Sensitivity: 2.06%ft. 10.Operating temperature: -10℃ ～ +50℃. Operating humidity :≤95％RH. 11.Execute criterion:GB4715;EN54-7;UL268;EN14604;UL217. 12.Dimension: Φ100*43mm.