This part can be used with any of the following masks: 6100 Sm Mask 6200 Med Mask 6300 Large Mask 6700 Sm Mask 6800 Med Mask 6900 Large Mask 6211 Med. Mask 6311 Large mask 7501 Sm Mask 7502 Med Mask 7503 Large Mask Particulate Pre-Filter - pre-filter for 6001 cartridge (10/pkg)