... steel,Japan SUH660,America A286,35#,40CR,35CRMO,SCM435,Brass,and etc. Camera ScrewSurface treatment Plain, Black Oxide,nickel plated, Chromated, passivated ... plating, phosphated, Dacromet,copper plating, gold plating and etc as per your need. Camera Screw salt spray time 2 hours, 24 hours ...