3M Radial Bristle Discs, 38 piece assortment kit, 3/4"3M Scotch Brite Radial Bristle Discs, 3 4 diameter, 1 16 arbor hole. Mandrel that is required is included. This works perfect with the quick change hand piece. Which can be purchased separately or with this kit, please select the option before adding to cart. This 38 piece assortment kit includes the following; 80 grit yellow (6 each) 220 grit red (6 each) 400 grit blue (6 each) Pumice 1,200 grit pink (6 each) 6 micron, 3,000 grit peach (6 each) 1