The rubber backer is 5/8-11 Thread. 27 Pieces of 5 / 5 Inch Polishing Pad. 1 Piece of 5 / 5 Inch Professional Grade Glaze Black Buffing Pad (it brings natural stone granite marble mirror like polished result). 1 Piece of 5″ Rubber Backer/Pad Holder (5/8″-11 Threaded arbor). Remind: Rubber Backer’s max capacity is 5000RPM. Please don’t use it with high speed grinder/polisher. Total: 28 Pieces +. 27 Pieces of 5 Diamond Polishing Pad for granite marble concrete stone. 4 X Grit 30 50 100 200 400. 2 X Grit 800 1500 3000. 1 X Grit 6000. 1 Piece of 5 Professional Grade Buffing Pad (make natural stone and granite marble mirror like polished). Recommend 3500 – 5000 rpm (grinder or polisher speed must be lower than 5000 RPM). Wet or dry use (wet use recommended).