HDG stands for Hot-Dip Galvanized, so an HDG Foundation Bolt is a foundation bolt that has been coated with zinc using a hot-dip galvanizing process — meaning the bolt is dipped into molten zinc to create a thick, durable protective layer on the steel surface. This zinc layer greatly improves resistance to corrosion, especially in harsh environments like coastal or industrial settings.Example products: • HDG Foundation Bolt with Nut ... Continue