twist drills:size :in metric,from 0.2mm to 20mm ... 8 inch M42,M35,M2(6542),etc fully ground,milled HSS straight shank twist drillStandard: DIN338size :in metric,from 0.2mm to ... ;in british,from1/64 to 5/8 inchusing material:,,HSS-M42,M35,M2,9341,4341,4241.production technics:rolled ... coated,black flute&white edge,amberfimish &black flute,rainbow drills,zirconium coated,black flute&white shankSet:1.5--6. ...