These premium gold aluminum oxide grain sanding discs are manufactured with the highest standards in the industry and are designed for heavy duty sanding and grinding of wood, metal, fiberglass and painted surfaces. The resin bonding system resists heat and moisture, which extends the useful life of the sanding discs. - Aluminum oxide durable grains are recommended by professionals for sanding a wide variety of surfaces including wood, metal, fiberglass, and painted surfaces - The vented-hole pattern allows for maximum dust extraction - The double resin bonding system resists heat and humidity, extending the life of the sanding discs - The pressure sensitive stick-on holding system holds securely without slipping, tearing, or wrinkling - The anti-clog stearate coating reduces particle build-up, keeping the grain exposed longer and improving performance