The Hillman Group 82220 6-Inch x 3/8-Inch Hex Washer Head Slotted Self Piercing Screw, 100-Pack
These Self-Piercing Screws feature an undercut head design to help provide great holding power and stability. There is no pre-drilling required, making these easy to use. Ideally, they are used for thin metal such as sheet metal and duct work.