... steel fasteners, titanium alloy fasteners, chemical riveting bolt department cases. 2, stainless steel: SUS302, SUS304 (A2-70, A2-80), ... customized fasteners. Surface treatment: 1, blue white zinc 2, 3, black color zinc zinc 4, mechanical permeability zinc 5, 6 and ... passivating galvanized 7, nickel, chromium plating, electrophoresis 8 9 10, black wardak gongs (zinc chrome plating coating) 11, 12, 13, ...