Gator, 4 pack, 5", 150 grit, aluminum oxide sanding discs, quality red resin sanding disc is designed specifically for power tools, for use on wood, metal, drywall, fiberglass & painted surfaces, fits 5" backer pads, the stick on adhesive holds securely without slipping so you can smooth large surfaces, resin bonded to resist heat & humidity for longer life, anti-clog stearate coating reduces particle build up, keeping the high performance grain exposed longer.