Pad Holder’s max velocity / capacity is 5000 RPM. Please do not use it with high speed grinder or polisher. This package carries (a)-(c). (a) 1 Piece of 7″ / 180mm Diameter velcro pad holder (5/8″-11 Female Thread arbor). (b) 12 Pieces of 7 / 180mm wet dry use wet use recommended. Ideal speed of grinder when using them is between 2800 and 5000 RPM. Diameter Pad for granite marble concrete quartz travetine. 3 X Grit 50. 2 X Grit 100 200 400. 1 X Grit 800 1500 3000. (c) 1 Piece of 7 Diamond glaze buffer (it brings mirror like polished result to natural granite marble).