The Mirka Bulldog Gold 5-Inch 8-Hole 60-Grit Grip Vacuum Discs provide a fast and exceptionally long-lasting cut. This high-strength resin bond system features a special sharp, durable aluminum oxide grain. The durable aluminum oxide, combined with urea resin over glue bonds and an open coat, creates a high performance sandpaper. With a B weight backing, the discs offer better edge wear and wear ability. Made with an anti-load stearate to provide increased life, these vacuum discs are designed to fit the DeWalt DW421, DW423, and 5-inch Ryobi and Bosch 3107, 3725. This pack includes 50 discs.