Driak 20pcs 4*12mm Cone Leather Buffing Wheels Polishing Set Fit for Dremel Shank Diameter : 3mm / 0.118"; Head Size : 4*12mm Package Content : 20 x Grinding Heads This kind of cow leather grinding head is more better that rubber grinding head Uses: The grinding can be polished to eliminate grinding, and do not burn jade pieces, you can quickly precision polishing any rough surface raw jade, jade pieces to be processed after the final finish can reach 8.