Pads can be wet or dry use (wet use recommended). This package carries (a)-(b). (a) 1 Piece of 5″ aluminum velcro pad holder (5/8″-11 female thread arbor, with water feed hole). 1 Piece of 5 velcro backed diamond turbo row grinding cup wheel for stone concrete travertine surface grinding. (b) 15 Pieces of 5 / 125MM Diameter Pad for granite marble concrete travertine they can be wet or dry use. Wet use make its life longer. 5 Pieces of STEP 1, STEP 2, STEP 3. Recommend 2800 – 5000 rpm (grinder or polisher speed must be lower than 5000 RPM). Wet or dry use (wet use recommended).