These drywall anchors are made of plastic and include number eight screws. They have an anchor length of 1 1/2 inches and screw directly into drywall with no drilling necessary. They have a wood screw and a grip range and a minimum wall thickness of 3/8 inches to 1 1/2 inches. They come in a package of 100. The zinc version is for drywall thickness of 3/8 inches, 1/2-inch, and 5/8 inches.