Supplies breathing air for several hours by rotating cylinders for up to (4) users at a time, at NFPA flow rates. Standard valved high-pressure inlet with stainless steel quarter turn ball valve (includes standard CGA male threads and dust cap with lanyard). Fail-safe, open, sealed regulator on respirator supply. End-of-cylinder service indicator. All connections are easily accessible. Accommodates (2) 4500 or 2216 psig cylinders. Optional tool-supply manifold. Lightweight and portable. Check-valved to prevent contamination from tool manifold. Features 4-outlets w/ Hansen QD, Aux. inlet, without cylinders.