The AccuSharp Deluxe Tri-Stone Knife Sharpening System features a course diamond-coated steel allowing you to easily sharpen and hone any straight-edge blade with ease. AccuSharps three stone surfaces include coarse diamond, medium alumina-oxide and fine ceramic. This Tri-Stone System provides extra durability and safety on any surface with a rubber-grip base which prevents sliding while sharpening and honing your knives. Additionally, the deluxe Tri-Stone Sharpener base can be mounted to most countertops for extra stability. Includes an angle guide to assist in maintaining a consistent angle while sharpening. Grits Diamond Coarse 320, Synthetic Medium 280, Ceramic Fine 1500.