Norton Economy Tool and Knife Abrasive Sharpener, 6" x 2" x 3/4" Size, Grit Combination Combination oilstone has 100 grit on one face for repairing steel cutting edges and 320 grit on the opposite face for sharpening and maintaining them Aluminum oxide produces durable, smooth-cutting edges, and is preferred for close tolerances 3/4 x 6 x 2 inch (H x W x D) size makes this stone suitable for use as a bench sharpener for flat-bladed tools, household utensils, and knives Compact for easy portability Oilstone is more durable and harder than a waterstone