Double Threaded HCR Trim Screw: SPAX PowerTrim Fasteners virtually disappear for clean interior and exterior trim applications. T-Star Screw: T-star plus drive provides superior bit engagement, better bit engagement means quicker installation with less effort, welcome to the world of one-hand overhead driving. Check out our Threads: Our patented thread technology allows the washer head screw to be driven faster, is easier to install, and reduces splitting in wood. Let SPAX take some of the hassle out of your next project. Wood Screw: No required pre-drilling in wood, be more efficient on the job by eliminating time consuming steps with self drilling SPAX unique 4CUT POINT technology. Yellow HCR Screw: Yellow HCR coating independently tested for use in treated lumber, composite wood and PVC. Engineered and Manufactured in the USA!