The product is made of high-speed steel.Smooth surface finish, long service life.Suitable for wood, malleable iron, aluminum, plastic, etc.Great replacement for your dull drill bit to improve work efficiency.Straight shank design is more suitable for many electric drills (here is not included).Specification:Shank Type:Tool Flute Type:Twist Drill Bits Diameter:Material:Shank Diameter:Total Length:Drill Bit Length:Package Content:HSS(High Speed Steel) Straight Shank Twist Drill BitNotice:Please keep cool and gentle using, the working life of the twist drill bits can be largely prolonged by proper usage.