Commercial grade silicon carbide sand paper. Will fit all 5" - 8 Hole hook and loop orbital sanders. Can be used for concrete, marble, limestone, travertine, and other hard stone surfaces. Each pack includes 10 discs. Meant to remove minor imperfection and help "open" the concrete before staining or sealing. If you wish to grind or polish, Diamond Polishing Pads must be used with a Stone Polisher.