... , Tin Coated, Bright, etc. twist drill bit setpecification: 1.5, 2, 3, 4, 5, 5.5, 6mmFinish: Black Finshed, Tin Coated, Bright, etc.Process: Roll ... -1 black oxideH101-2 edge groundH101-3 edge ground,tin coatedH101-4 fully ground,brightH101-5 fully ground,black finishedH101-6 fully ...