150Pcs 2in 80 Grit Aluminum Oxide Roll Lock Die Grinder Grinding Sanding Disc Pad Features & Benefits Sharp Aluminum Oxide Abrasive: Made from chosen sharp aluminum oxide abrasive which provides increased life, fast cut rate, consistent finish. Advanced Grain Planting Technic: Dense aluminum oxide grain helps increase working efficiency and deliver better deburring or grinding results Heavy Duty X-wt Polyester Cloth Backing: Heavy duty X-weight 100% polyester cloth features flexible, high strength, good elasticity, heat resistant, corrosion resistant, wear-resistant and washable. It helps offering operational comfort and longer disc life. Unique 2-Layer Polyester Cloth Structure: The biggest difference and advantage between roll lock sanding discs of ours and others is the unique 2-layer polyester cloth structure. The other layer of Blue Polyester Lining Cloth is used to further enhance disc strength and friction between sanding disc and rubber pad holder, to resist disc coming loose when operating which helps achieving longer lifespan and ensuring security Resin Over Resin Bonding: High strength resin bond system provides superior grain support, resist heat and humidity for longer life. More Resin Adhesive Added to Resist Cloth Coming Loose: Resin adhesive features heat resistance. More adhesive added to bond the cloth to the disc tightly, to resist cloth coming loose during operations