Remind: The velcro backer/pad holder are with water feed hole, can be used for wet polishing. Pad holder’s max capacity / velocity is 5000 RPM. Please DO NOT use it with high speed grinder or polisher. This package carries (a)-(b). (a) 1 piece of 4 Diamond Glaze Buffer (it brings mirror like polished result to natural granite marble). (b) 48 Pieces of 4 Diamond wet dry (wet use recommended) Polishing Pad for granite marble concrete. And 1 Piece 4″ Backer (arbor is 5/8″-11 Female thread). The 48 Pads are. 10 Pcs X Grit 50 100 200. 9 Pcs X Grit 400. 3 X Grit 800 1500 3000. Remind: velcro backer’s max velocity / capacity is 5000RPM, please don’t use it with high speed polisher/grinder. 3.2mm thickness. Recommend 3500 – 5000 rpm (grinder or polisher speed must be lower than 5000 RPM). Wet or dry use (wet use recommended).