Grinding Wheel is specifically designed with a 7/8 In. arbor hole to fit the DELTA 23-700 Universal Grinder. The grinding wheel lets you sharpen your knives and other blades and bladed tools to a razor- sharp edge. The wheel is 10 In. in diameter with a 2 In. face width, and has a 220 grit surface for a clean, sharp edge. It is a wet wheel design so is bathed in water to keep the cutting edges cool and prevent the tool's temper from getting damaged. It runs cooler and grinds cleaner than standard wheels thanks to its vitreous aluminum oxide composition.