1These burrs are made of high speed steel for high hardness, high abrasion resistance and high heat resistance 2There are total 5 pieces single cut burrs in various shapes that you can use for many purposes 31/4 inch hex shank would fit many electric powered or pneumatic powered tools and machine tools 4This set of rotary burrs could be used on aluminum and iron materials 5Widely used for carving, shaping and for the removal of sharp edges or corners, burrs and excess material Features: These burrs are made of high speed steel for high hardness, high abrasion resistance and high heat resistance. There are total 5 pieces single cut burrs in various shapes that you can use for many purposes. 1/4 inch hex shank would fit many electric powered or pneumatic powered tools and machine tools. This set of rotary burrs could be used on aluminum and iron materials. Widely used for carving, shaping and for the removal of sharp edges or corners, burrs and excess material. Specifications: Material: High speed steel 4241 Color: As Picture Shown Hex Shank Size: 6.35mm(1/4") Other Size: As Picture Shown Quantity: 5pcs Weight: Approx. 150g Package Includes: 5 * Burrs (cordless drill is NOT included)