Crown Bolt 87560 01560 3/8-Inch by 4-1/2-Inch Zinc Plated Steel Hex-Head Lag Screws, 25-Pack
Lag screws are used for directly fastening into wood surfaces. Used with a lag shield, lag screws can be used in masonry applications. The length of a lag screw is measured from the under head bearing surface to the tip of the screw.