Best choice for aggressive sanding, preparation, and stock removal.Zirconium grain for aggressive material removal and long life.Heavy, F-weight paper prevents torn edges which produce deep, uneven random scratches.Available with Hook & Loop Backing or PSA Backing., Strong resin over resin bond construction is resistant to heat and moisture.This special sharp and durable grain cuts fast and lasts long.Hook & Loop Fastening System: Allows for quick changes and less downtime..Individual PSA Discs: Tabbed for easy removal of release paper.Backing Pads, Interface Pads and Contour Hand Pads for Paper Discs are available in Accessories.