These diamond-coated wheels for the T-4 sharpening machine are an excellent choice for sharpening all types of steel and ceramic blades, but they are especially effective for working with tough alloys. Each has a machined steel frame coated with a single layer of durable, fracture-resistant monocrystalline diamond that has been bonded in nickel. Requiring no truing, the wheel maintains a consistent shape and diameter to allow grinding on the sides of the wheel as well as on the edge. Available in three grits, each producing a consistent scratch pattern. The coarse wheel (360x) is best suited to fast steel removal for efficient sharpening, repairing and reshaping of edges. The fine version (600x) is an excellent go-to wheel that provides both effective steel removal and a polished finish, and the extra-fine wheel (1200x) provides minimal steel removal and gives blades a bright mirror finish. The diamond wheels should always be used with water. One bottle of Anti-Corrosion Concentrate is included and should be added to the water to prevent rust forming on the wheels.