E511 particlate filter+E501 Filter Retainer Cover+6001/6003 Cartridge+Face Mask Typical industrial applications for filters are: Agriculture, Construction, Food Industry, Foundries, Pharmaceutical, Powdered chemicals, Quarrying ceramics, Refractory materials, Woodworking. Versatile, lightweight and effective against a wide range of oil and non-oil based particles. Carbon layer protects against nuisance vapors. Filter retainer cover used to hold Particulate Filters 501 Filter Retainer. Half Face Reusable Respirators offer the user comfort and convenience coupled with the cost savings of a reusable respirator. Reusable - just dispose of the cartridge and filters when used to capacity. The swept back design of the cartridges improves balance and visibility. Can be disassembled, cleaned and reused. Very light-weight. Easy to adjust head straps.