AC Operated Combustible Gas Alarm Semiconductor gas sensor Operated with 220VAC 50Hz mains Detecting Natural Gas or LPG or Man-made Coal Gas(custom-made and optional) NO/NC signal, pulse signal, wireless transmitting signal alarm output available(optional) Resistance against cooking smoke Or ethanol steam Wall mounted installation Operation indicator Sensor fault indicator Alarm with sound & light indicator Self-test button CE approved, Comply with UL1484 Stand, BV ISO9001: 2000