The CleanSpace CST Head Harness is designed to be used with the latest model CleanSpace ULTRA and CleanSpace PRO PAPR Power Units. The Head Harness comes with every CleanSpace CST Half Face Mask purchase. The part is a spare used for as replacement in case of damage or loss. The Head Harness is made of high density polyethylene (HDPE) straps, silicon adjustable band, polycarbonate 20% glass filled piton, and nylon 66 hook & cleat. Used with the revolutionary CleanSpace PAPR: light weight, no hoses or belts Designed for comfort over long periods Allows sweating and breathability Multiple adjustment points Easy to wash and quick drying Durable and designed for long wear in harsh environments Easy and quick replacement