In low oxygen conditions or when air quality is compromised, SAR (supplied-air respirator) systems deliver safe breathable air. A supplied-air compressor is connected to a worker's facepiece through an airline hose. The worker's mobility is restricted by the length of the airline, but the compressor provides an endless supply of air. SAR (supplied-air respirator) devices come with everything a worker needs to put together a unit. An air pump, breathing tube, hose, and respirator are all part of the system.