Zinc Plated Bolts: Standard zinc plated screws, washers, bolts, and nuts are hardware that have been plated in zinc. The zinc corrodes at a slower rate than the steel, so it is rust resistant. Besides the beautiful look the zinc plated hardware adds to products, it also has more practical benefits as well:

• Alkaline zinc-nickel plating was found to be the most salt-spray resistant of the several non-cadmium platings tested.
• Alkaline zinc-nickel plating provides equal or better corrosion resistance as cadmium plating.

Hot-dipped galvanized hardware is coated with a thicker layer of zinc than normal. This additional zinc coating improves it's resistance to corrosion.