Diameter: #10 Length: 1 Material: Steel Finish: Zinc Head Style: Wafer (# 3 Phillips Bit) Point Type: Drill Thread Size: 24 (Fine) Thread Length: Full Type: Self-Drilling Screw A self-drilling screw or tek screw is similar to a sheet metal screw but it has a drill-shaped point to cut through the substrate to eliminate the need for drilling a pilot hole. Ideal for any project involving light gauge sheet metal awnings door and window frames gutters sheds.