Source of power: AC 220V Propane sensitivity: HEL (UEL): 9.5 VOL% / LEL: 2.1 VOL% Butane HEL (UEL): 8.4 VOL% / LEL: 1.8 VOL% HEL (UEL): 15.0 VOL% / Methane LEL: 5.0 VOL% 1.7W of power is used. Temperature range for operation: -10 to 50 Humidity level in the air: below 95% RH At ten feet, the horn level is 75 dB. Green LEDs in standby mode and red LEDs flashing and an acoustic alarm in alarm mode Gas Type Sensed: LPG, Town Gas, and Natural Gas Dimensions: 11x7x4 cm