20 pcs Double cut head rotary burrs milling cutters set. Fits for dremel and most small rotary tools. Made of tungsten and carbide which use for rotary burr, high hardness and high abrasion resistance. Shank diameter: 3mm(1/8 inch), Cutting edge diameter: 6mm, Rod length: 100mm/ about 4 Inch. High performance on processing copper, aluminum, alloy, iron, marble, jade, steel, glass, wood and plaster etc. Widely used for metalwork, tool making, model engineering, wood carving, jewelry making,welding, chamfering, casting, deburring, grinding, ect Shank Diameter: 3mm (1/8 inch) Head Type: Double Cut Cutting Edge Diameter: 6mm (1/4 inch) Shank Length: 100mm (about 4 Inch) Processing Hardness Up HRA greater than equal 85 Material:steel colour:Silver Package Contents: 20 x Tungsten Carbide Rotary Burrs Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.