DMT D12EF-WB 12 inch Dia-Sharp Bench Stone - Extra Fine/Fine With Base Extra-Fine diamond (9 micron / 1200 mesh) to polish and refine a razor edge; Fine diamond (25 micron / 600 mesh) for a razor sharp edge Magna Base System allows for 2" knuckle clearance and easy to change and remove the bench stone for quick grit changes 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