We speicalize in making kinds of hss twist drill bits, including general, long, lengthened and extra-long ... the strongest products of the company.Executive standard:GB/T1438.1-1996, GB/T1438.2-1996,DIN341,DIN345...Finishing Color:Tin ... coatedMaterial:M2,M35,M42,Hss-9341,4341,4241.. hss taper twist drill bits