... made of thicker steel plate. Zinc-Galvanized Surface Treatment, Non-rust & Beautiful Outlook.. All garage door hardware are made of thicker ... steel plate.The surface treatment is Zinc-Galvanized Process, Non-rust. Garage Door Hinges include 1#, 2#, 3#, 4#, 5# Hinges ... factory. Garage Door Accessory --- Hinges, Brackets, Tracks, Hardware/Parts ---Non-rust