... two head threaded stud bolts1) Material: High quality carbon steel Class :4.8, 5.8, 6.8, GR. ... 8,A325-1,A490-1 ,GR.B7,GR.B7M3) Material :stainless steel :302 ,304 ,305 ,316, 304L ,316L ,410, ... A2-70 ,A4-70 ,GR.B8,GR.B8MSurface Refine : Part galvanization ,Colorful galvanization ,Army green galvanization ,Black galvanization ,Steam ... plastic box. 3)As to customers' requirement stainless steel stud screw