The Cortex Hidden Fastening System is the fastest, easiest way to hide the heads of your deck screws across the entire deck, first and last board, perimeter and stairs. Cortex plugs are made from the same material as market-leading deck boards.; ; Brand Name: FastenMaster Sub Brand: Cortex Drive Type: Torx Size: T20 Length: 2-1/2 in. Product Type: Driver Bit Number in Package: 2 pk Packaging Type: Carded