12 X 1 1/2 Pan Head Square Drive Tapping Screw 18-8 Stainless Steel

Self-Tapping Screws, also called Sheet Metal Screws, tap their own mating thread in pre-drilled holes. They can be used to securely fasten metals together, including aluminum, efficiently fasten metal to other materials, such as wood or plastic, by creating a much stronger bond than a regular nail.