Protects 3M Versaflo Particulate Filter, TR-6710E from physical damage, Holds a 3M Versaflo Prefilter, TR-6600 or 3M Versaflo Spark Arrestor, TR-662 in place for further protection, Enables 3M Versaflo Power Air Turbo to be worn through decontamination showers, Filter Cover may be cleaned and reused.