Westward 20UH85 Carbide Bur Set Double-cut carbide bur sets feature left- and right-hand flutes that cross over to efficiently remove material from steel, stainless steel, and other high-strength ferrous metals, resulting in a smoother finish compared to single-cut burs. Head Shapes Included / Cylinder, Oval, Round Nose Tree, Cone End Type / Flat; Pointed; Radius Cut Type / Double Trade Numbers Included / SA-1, SA-3, SC-1, SC-3, SE-1, SF-1, SF-3, SL-3 Shank Diameter / 1/4 inch Head Diameters Included / 1/4 inch; 3/8 inch Largest Head Diameter Included / 3/8 inch Smallest Head Diameter Included / 1/4 inch Included Angle / 14 ° Shank Material / Steel Head Material / Carbide Head Material Grade / YG7 Coating / Bright (Uncoated) Includes / Plain Case Number of Burs Included / 8 Compatible Tool Type / Die Grinder; Rotary Power Tool; Straight Grinder Maximum Operating Speed / 40,000 RPM Primary Material Application / Brass; Bronze; Copper; Nickel; Steel; Titanium; Zinc