3M Clean Sanding Filter Bag Backpack Assembly 28365, 1 per caseThorough dust collection enhances the performance of 3M Clean Sanding Discs (sold separately) Achieves superior dust collection when used with 3M Random Orbital Sanders with Self Generated Vacuum Large and Extra Large sizes save time because operators can change bags less frequently Can be used with 3M Clean Sanding Filter Bag Backpack Assembly (sold separately), which holds and protects the Filter Bag for ultimate portability X Large size Thorough