The aluminum backer’s arbor is 5/8-11 Female Thread. 28 Pieces of 5 Diamond Polishing Pad for granite marble concrete. 1 Piece of 5 Professional Grade Glaze Buffing Pad (it brings natural granite marble mirror like polished result). 1 Piece of (5/8″-11 Female Thread arbor) 5″ Aluminum Backer/Pad Holder. 28 Pieces 5 Diamond Polishing Pad for granite marble concrete. 6 X Grit 50 100. 5 X Grit 200 400. 2 X Grit 800 1500 3000. Recommend 2500 – 5000 rpm (grinder speed must be lower than 5000 RPM). Wet or dry use.