6pcs of higher quality of rotary file set for rotary tools Special alloy steel is hardened and tempered for long life Precision cutting edges will not clog or load up This has 1/4" shanks to fit all electric and cordless drills For processing of metallic and Non-metallic surfaces using an engraving machine For rasping or filing wood or soft metal For electric grinding of metal, plastic, wood, metal and other soft grinding Color: Shown in the picture Type: Rotary Burr Shank Diameter: 6 mm / 0.24 inch Quantity: 6 pcs Material : High Speed Steel Application: suitable for grinding metal, plastic, wood soft metal etc. Size(length): 60 mm / 2.36 inch Net Weight: 123 g / 4.34 oz