The MSA Altair 4XR Multiple Gas Detector (LEL, O2, CO, H2S) surpasses industry standards in several crucial areas. Its four-year sensor life is 60% longer than the industry average, while its 24-hour run time exceeds the industry average by 71%. This versatile portable detector is a perfect match for industries ranging from fire fighting to welding, and its digital sensor output makes it less likely to suffer from RF interference. The unit features exclusive MotionAlert, which lets others know if the user has become immobile, and InstantAlert, a manual alarm that alerts others of potentially dangerous situations. This rugged unit is designed to withstand a drop of up to 20 feet and uses less than half as much calibration gas as the industry average.