Hollow Bolt,Stainless 1.ISO,ANSI,CE,JIS,DIN,BS& non- ... 8 ,6.8,8.8,9.8..... Hollow Bolt,Stainless Steel Hollow Bolt,Bolt with Internal Thread.1.What’s the specification ... ,1039,40ACR...Alloy steel are 35,40CrMo,SCM435,10B38...Stainless steel is SS201,202,302,304,316...copper is ... Socket typesPhillip type,Pozi type,Eleven type,hexagonal type,Torx type,trangle type,slotted point type,square type,Combined ...