... kinds of HSS twist drill bits, the details include:1) Standard: DIN338, DIN1897, DIN340, ISO235, ANSI B94. 11M, DIN345, DIN 18702) Material::HSS 4241, HSS 4341, HSS 9341 ... oxide, black flute & bright shank, rainbow6) flute type:N or VA7) Shank: straight shank drills, taper shank drills, reduce shank drills, 1/2 shank drills, hex shank drills