Bolt:M6-M64 full thread or half thread Nut:M3-M64 hexagonal, flange washer:M3-M33 flat, big outside diameter, spring 1. Treatment: cold forging/hot forging2. Materials option: Stainless Steel C276, 904L, 304, 304L, 310S, 316, 316L, 321, 317L, 2507, 2205, 254SMO, AL6XN, 1. 4501, 1. 4529.Super duplex stainless steel F55, F51, F53 HastelloyB & C, Inconel, Incoloy etc.3. Standards: GB, DIN, JIS, AISI ...