ASelected 5 Pcs Double Cut Carbide Rotary Burr Set 1/4inch Shank and 5/16inch Head Die Grinder Bits High Hardness and Good Toughness Perfect for DIY Wood-working Carving, Metal Polishing, Engraving Metal Die File Specifications: Shank Diameter: 1/4 Inch (6MM) Cutting Diameter: 5/16 Inch (8MM) Cutter Pattern: Double Cut Material: Solid Tungsten Carbide Steel Length: 58,62,63,64,65MM Package: Packed in portable plastic cases. Cutting Burr Shape: 5 Different Shapes 5PCS Carbide Rotary Tool 1 x Rotary Burr - Cylinder with Round Head 8mm x 6mm. 1 x Rotary Burr - Cylinder With Endcut 8mm x 6mm. 1 x Rotary Burr Ball Nosed Cylinder 8mm x 6mm. 1 x Rotary Burr - Pointed Tree 8mm x 6mm. 1 x Rotary Burr - Ball 8mm x 6mm. Grinder Drill Bits Applications: Rotary file can be widely used in the processing of all kinds of metal and non-metal, such as alloy steel, stainless steel, wood and marble. 1/4" Shank tungsten carbide bits fit for die grinder and drill, widely used in automotive, machinery, chemical and other industries. Perfect for metal working mold and pattern making, die sinking, DIY wood-working carving, metal polishing and engraving. Carbide bits are machined from toughened and hardened steel shanks, which prevents bending and reduces vibration and improves tool life. Suit for Cast Iron, Cast Steel, Carbon Steel, Wood, Plastic, Glass, Stone, Alloy Steel, Stainless Steel, Marble , Jade .etc. Suit for Wide Range of Materials Hard Wood Stone Glass Stainless Steel