Hollow Bolt,Stainless 1.ISO,ANSI,CE,JIS,DIN,BS& non-standard ... .8 ,6.8,8.8,9.8..... Hollow Bolt,Stainless Steel Hollow Bolt,Bolt with Internal Thread.1.What’s the specification of ... professional manufacturer with more than 20 years experiences in screw,bolt,nut,washer,rivet, stud, pin,wrench and so on .2 ...