Diamond Resin Polishing Blocks Size: L140 & L170 Grit: #500, #800, #1500, #3000 Diamond Resin Polishing Blocks with rein bonded are specially used for fine grinding of stone slabs and porcelain tiles instead of normal abrasives.Size: L140 & L170Grit: #500, #800, #1500, #3000Any question, pls feel free to contact me.Henry Chan (sale08) Diamond Resin Polishing Blocks for Granites & Porcelain Tiles