MSA ALTAIR 2X Gray Gas Detector with 0.1 ppm resolution is designed to detect the presence of Carbon Monoxide. It has XCellsensors that offer superior stability, accuracy and sensor life. Gas detector featured with 0 - 20 ppm sensor range is ideal to work at a temperature range of -10 to 40 deg F. It features rugged rubberized armor with one-handed and one-button operation.