Package Contents: 30 x Circular Sanding Discs (225mm, 80 Grit, 6 Holes). High Quality: The sanding disc features a thick, D-class paper backing, made of high-quality alumina with abrasion-resistant sand, and a high-strength resin bonding system for increased durability. Easy to Replace: Durable backing makes sanding disc replacement easier and more convenient; hook-and-loop backing for quicker assembly. For Size: Diameter 225mm/9in, with 6 pre-drilled holes for dust extraction, suitable for random orbital sanders/sanding/polishing/rust removal. Multi-Purpose Sanding Discs: Suitable for sanding and polishing wood, jewelry, glass, stone, cars, machinery, metal, non-metal, rubber, leather, plastic, etc.