APPROVED 5/16"-18 Steel Carriage Bolt, Grade 5, 2 InL, Zinc The oval head design looks clean and finished, while that square neck under the head is the magic feature - it locks into place when you tighten the nut... Oval head style for recessed finish with a slightly rounded surface The last 2 digits identify the percentage of carbon for the alloy (in hundredths). Double-End Stud 7/16-20 SAE x 7/8 ~ 7/16-14 USS x 3/4 9701 Carriage Bolts have a domed head with a square neck to prevent spinning Coarse threading also allows for thicker coatings and platings. Steels are designated by a 4 number SAE Steel grade. Fast Free Shipping on all fasteners, rivets, wood screws, self tapping screws, socket caps, machine screws inch & metric. Use in square holes for wood-to-wood and wood-to-metal fastening. Can be used as a security fastener. The smooth head prevents unfastening from the head side. The first two digits indicate the primary materials used to form the steel. The steel used in these fasteners has a tensile strength ranging from 100,000 to 150,000 psi (pounds per square inch). Coarse threads are better for brittle materials, and will assemble and disassemble more quickly than fine threads Made from zinc plated steel for durability; The self-locking square neck and coarse ... ​ A307 Grade A Hot Dip Galvanized Steel Carriage Bolts (100-​Pack
