Phosphated Galvanized Perfect Quality and Bottom Price Black Drywall Screw/ Zimbabwe Market Drywall Screw Material: Q195 or Q235, low carbon steel Head: Countersunk and Checkered head, or flat head Shank: Smooth, Twisted, or Ring Length: 3/4"-14" Nail Point: Diamond and sharp point Surface: Polished, Galvanized, Vinyl coated, or others