8" Replacement Grinder Stone

8" diameter, 1" thick with a x 5/8" center hole. Ruby - Aluminum Oxide Grinding Wheel for commercial lawn mower blade sharpeners. The manufacturer states that the blade grinder wheel is rich ruby red in color, much harder, and extra tough. Designed for the performance qualities to sharpen quicker while reducing burn because of the open structure design. The relative percentage of abrasive and bond, and their spacing within the wheel, impart a characteristic known as structure according to the manufacturer.