Size: 3/8 inch X 1-1/2 inch Heavy duty wood screw with 6 sided hex bolt head Features deep wood screw threads and does not accept a nut Used in applications where standard wood screws cannot support the load (deck building, etc.) Requires pilot hole to be drilled and installs using wrench or socket tool Thread Type: Deep, Point Style: Gimlet Specification(s) Met: ASME B18.2.1 and ASTM A307A