Just to emphasize swall's response, it is standard to use a non-electrolytical zinc-rich coating rather than hot-dipped galvanizing on high-strength fasteners. The high temperature of the molten zinc may reduce the strength of the fasteners. Dacromet is only one of multiple types of non-electrolytic zinc-rich coatings. You should consider products from Magni and Doerken as well.
Regards,
Cory
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