These diamond/resin bonded pads are used to sand and pre-polish gemstone. They are heavily coated for extremely fast results. They should be put onto a mandrel and then used with a flex shaft or motor. Always use with water and do not let get hot! We supply grits up to a pre-polish. These pads also have an adhesive back so that you can back it with plastic to make the pad more efficient and longer lasting. THESE COME IN PACKS OF 2.