Diamond Machining Technology's (DMT) multi-patented DuoSharp Bench Stone is a precision flat, two diamond surfaced sharpener. The company says no oil is needed and it is guaranteed to provide consistent, even sharpening every time. At 10 inches, the bench sharper offers a large, wide diamond surface for sharpening a variety of edges including shears, cleaver and specialty knives, plane sole, machete, and more. Available with a bench stone base accessory, the bench stone is offered in three grit combinations: coarse/extra-coarse, fine/coarse, or extra-fine/fine.