Mirka 23-321-060 5 Bulldog Gold 5-Hole 60 Grit Heavy-Duty PSA Vacuum Disc - Gold is designed for finishing and heavy stock removal. The durable aluminum oxide grain delivers a fast exceptionally long lasting cut. Proprietary backing is stronger than other competitive brands using traditional backing. High strength resin bonding for superior grain support. A special stearate coating is used to maximize resistance to clogging and loading. A uniform semi open coat design produces an even consistent scratch pattern.