gas detector 1)Ranges:Sensor dependent 2)Power supply:10.5...45VCD ... 5)Unit:ppm, mA, %,%LEL,%VOL Programmable alarm operation value 4-20mA Smart Toxic Gas DetectorTechnical features * 4-20mA, 2 wire connection ... : Aluminium for O2,CO and combustible gas. Stainless steel for others. * IP rating: Ip66 Smart Toxic Gas Detector with alarm operation value 4-20mA