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