Remind: The 5/8"-11 Thread velcro backer/pad holder are with water feed hole, can be used for wet polishing. This package carries (a)-(c): (a) 1 Piece of 5" Velcro Backer / Pad Holder (5/8"-11 Thread, with water feed hole). Important remind: Pad holder's max capacity is 5000RPM. Please NEVER use it with high speed grinder / polisher. (b) 5 Pieces of 5" Diamond Ultra High segment (segment is 9mm high) cutting blade for granite concrete stone quartz travertine (inner hole diameter 7/8" to 5/8") (c) 16 Pieces of 5" Diamond PolishingPad for granite marble concrete glass. the 16 Pads are: 3 X Grit 50 100 200 400, 1 X Grit 800 1500 3000 6000. Remind: velcro backer's max capacity is 5000RPM, please don't use it with high speed polisher/grinder. - 3.2mm thickness - recommend 3500 - 5000 rpm - wet or dry use (wet use recommended)