MSA Custom 4500™ II

MSA's II Air Masks feature a sleek design and provide high performance in a unit that is lightweight and comfortable. The Air Masks are pressure-demand apparatus designed to maintain a slight positive air pressure inside the facepiece during inhalation and exhalation, which helps prevent contaminants from seeping in around the facepiece. Performance is maximized by splitting the regulator stages, with the first stage mounted on the cylinder backplate, and the lightweight second stage belt-mounted for convenient positioning. An intermediate-pressure hose connects the two stages.

For added versatility, the optional dual-purpose versions' regulators have two inlet ports-one for the fully-wound composite cylinder, and another for an air supply line. A connector allows the air supply to be semi-automatically switched from the cylinder to the airline.