: Made of 1045 steel with fire-dipped black surface treatment to ensure it is sharper and more durable; Total length: approx. 58 mm, top diameter 12 mm, top length 25 mm, shank length 29 mm, shank diameter 1/4 in (6.3 mm); Great for woodworking and wood carving: This rotary burr set is ideal for sanding, polishing, shaping and polishing softwood, plastic and rubber surfaces, not suitable for hardwood; EASY TO USE: This rotary file set features a 1/4 shank that fits all drill bits. You don't have to worry about whether this won't fit your drill, helping you enjoy woodworking; Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.