MSA ALTAIR 2XT Gray Gas Detector with 0.1 ppm resolution is designed to detect the presence of Carbon monoxide and hydrogen sulphide. It features XCelltwo-tox sensors that eliminates the need for a second detector. Detector produces digital output to minimize cross channel interference. Gas detector featured with 0 - 20 ppm sensor range is ideal to work at a temperature range of -40 to 140 deg F. It is made of tough over-molded rubber armor to survive multiple 25' drops onto concrete. Detector has large LCD display, characters and status icons for extra convenience.