Guaranteed not to hollow or groove, DMT's precisely engineered Dia-Sharp Bench Stone with continuous diamond surface assures consistent, even sharpening every time. The 8" length is great for both long and short knives providing cutting edge performance for a quick, keen edge on small contact areas and pointed tools. Perfect for flattening plane soles, irons and chisel backs￢ﾀﾝeven conventional and water stones. Includes non-skid rubber feet. Diamond grit clearly marked on side of stone. Extra-Extra Coarse grit. Extra-Extra Coarse diamond (120 micron / 120 mesh) for extreme removal of material and edge repair. Sharpening surface accommodates range of edges￢ﾀﾝ from large knives to small pointed tools. Sharpens knives faster than conventional stones with DMT's monocrystalline diamond surface. No oil is needed-sharpen dry or with water. Durable construction will provide years of consistent performance and reliable service.