Low Battery Indication : The buzzer doesnt sound and the three LEDs                                                flash at the same time
Power Supply : 9V battery (6F22 or equivalent), or external power source                           of dc 9V
Working Temperature : 0℃~50℃, relative humidity<75％
Storage Temperature : -10℃~60℃, relative humidity<85％
Size : Display unit : 185X61X31mm
         Sensor unit : 82X61X37mm
Weight : About 180g(without battery)