... prevent corrosion,Nickel-Copper-Nickel (Ni-Cu-Ni) [standard], Epoxy, Zinc (Zn), Gold (Au), Silver (Ag), Tin (Sn), Titanium (Ti), Titanium ... -Cu-Ni plus PTFE, Tin (Sn) plus Parylene C, Zinc Chromate, Phosphate Passivation and Uncoated (i.e. bare – not recommended but is ...