These 7/8" diameter, coarse grit Garnet discs are manufactured with the grit resin-bonded onto one side of thin yet stiff paper-backed discs. (Garnet is a natural mineral which is slightly less aggressive than Aluminum oxide.  Recommended for general use and with acrylics and gold.) These stiff paper backed discs are long-lasting and hold their shape well.  Ideal for maintaining flat and angled geometry.   Since they are manufactured with the Moore Snap-on brass center, they need to be used with a Snap-on mandrel (sold separately).  Max. operating speed: 30,000rpm.  Sold in box of 200 discs.