L.H. Dottie TEKHW122 Self Drilling Screw, Hex Washer Head, 12 by 2-Inch Length, 5/16-Inch Hex, Zinc Plated, 50-Pack Self drilling Hex washer head Zinc plated steel Invincibox up to 2-Inch length number 12 by 2-Inch length, 5/16-Inch hex