GRK Fasteners #9 x 3-1/8-in Polymer Exterior Trim screws ( 1900 -Per Box )

#9 x 3-1/8-in Polymer Exterior Trim screws ( 1900 -Per Box ). Specially designed for attaching composite and cellular PVC materials. Reverse thread design prevents mushrooming to create an even surface. Trim head provides a clean finished look. For interior/exterior use. Zip-tip allows for no-pre drilling and one step installation. Star drive eliminates stripping for improved productivity. W-cut low installation torque allows for fast driving and ease of install. Limited lifetime warranty