HSS Center Drill centre drill A type B type 1.Material: Hard alloy,HSS6542,9341,4341 ... treatment: bright finish HSS Center Drill centre drill A type B type1.Material: Hard alloy,HSS6542,9341,4341, ... treatment: bright finish 3.Size: A type 0.5-6.0 B type 1.0-6.34.Technicial:fully ... ,drill bits and reamers.Wlecome to visit our factory for further cooperation. HSS Center Drill centre drill A type B type