6-lobe drive prevents driver bit cam-out and stripping in recess. Type 17 tip provides fast starts and prevents splitting in hardwoods. Coarse threads run approximately 2/3 up the shank to help draw the decking tightly to the substrate. Pre-drilling is recommended near board-ends to prevent splitting.  316 stainless steel is ideal where superior corrosion resistance is required. Drive Sizes: #8 - T20, #10 - T25.Simpson Strong Tie Co., Inc.