Fast response of flammable gases leakage with a high efficient pump inside Self diagnosis function with built-in Microprocessor Easy replacement with a cartridge type sensor Digital flow sensor to maintain regular flow rate Detection gas from low to high concentration owing to various detection principle Stable quality and proved detection principle for service life Fine LCD display for showing various information 4-digit digital gas concentration display 4-20mA (Current source or Sink) output signal Easy configuration of monitoring by RS-485 Modbus or PoE 2-stage alarm, 1-trouble display and relay contact output 3-wire connection for signal & power Calibration and maintenance by one-man