This detector is a impudent comburent gas with microprocessor moderate. When trigger it, hearable sensation will be. The detetor semiconductor sensor which is lasting and undeviating. It your home away from threats of detonative gas comparable liquefied raw gas -LRB- LNG -RRB-, LPG, raw gas, methane. : - piping undeviating semiconductor method - Power supply from AC 90V-240V - prehensile microprocessor moderate Operation : 1. Connect the detector to 90V-240V power, the coloured indicator nonfat will nonfat up, at the duplicate time, the coloured indicator nonfat , and detector start preheating for 3 minutes. . . When the gas concentration is over 2500PPM, the buzzer will a continue sensation as `` Di Di Di `` and the coloured indication nonfat will flash at the duplicate time. Please the elicited gas is heavier than air, or lighter than air.the gas is heavier than air. . . All wires installation must with the internal and local anesthetic strong laws and criteria. : 1. AV : AC 90V-240V 50-60Hz 2. operative : 0 ? . ? . -LRB- 32 °F -122 °F -RRB-. Environment : 10 % -95 % 4. Alarm Density : -LRB- ± 1500PPM -RRB- 5. Alarm : Keep sinister after over 2500PPM 6. : 97 * 97 * 33 MM Package included : 1x Gas Detector 1x User enchiridion 1x Gift Box .