Main Features1. Manual testing and automatic reset2. Automatic error-detecting function3. Alarm sounds up to 85dBa @ 3mtr4. Micro-control chip to solve the problem of false alarm and omission5. Sensor with High reliability and stability6. Auto re-charge Li Battery capacity 1, 200mha7. Battery mode for over 24 hours continues8. Battery mode allows the system to be fully functional when the power is restored no delaysGas detected: Combustible gases like Natural gases e.g. LPG bottle gas, CNG, Propane. Etc.Refrigerant detected: R290 (LPG or Propane) R600 R600a R1270. Etc.Japanese Electrochemical sensor for accurate sensing Alarm output available (NCNO relay) Plugs specify on order. Voltage 220-240VAC or 110VAC.