Crown Bolt 84490 12520 5/16-Inch by 6-Inch Lag Screw Hex Head Zinc Plated, 25-Pack Zinc Plated 5/16-Inch X 6-Inch Hex Head Lag Screw For wood applications 5/16-Inch-18 Body Diameter And Thread Pitch 6-Inch Fastener Length Zinc Plated Finish