Stud bolts 1.Astm A193,Din931/933/975 2.Finish:Self ... ,Black,Teflon Coating(PTFE) Black, White,Blueness Zinc,Nickel Plating Stud Bolts & Nuts Size 1/2"-2" Specification ASTM A193 B7 ... /B16/B8M;ASTM A194 2H/8/8FProduct Description Product Name:STUD BOLT & U_BOLTS:1. Din 975, class 4.8, class 8 ...