infrared (IR) open-path flammable gas detector Searchline Excel ATEX. Transmitter (TX) and Receiver (RX):, Detection Range:short range5 to 40 meters, Detectable gases: Methane, ethane, propane, butane, pentane, ethylene, propylene, ethanol, and methanol., Approvals: Certification ATEX, Materials:316 stainless steel, Outputs:4-20mA