U-bolts are bolts bent in the shape of a "U" with machine threads on both ends that nuts can be threaded onto in order to fasten the u-bolt. Since u-bolts have primarily been used to support and secure pipe, u-bolts sizes are called out by the size of pipe. In addition to pipe, u-bolts have a wide range of uses such as securing tubing, roundbar, wood or steel posts, and can be embedded into concrete as anchor bolts. U-bolts are designed to be inserted into pre-drilled or punched holes. Made from carbon steel with a zinc plated finish. Zinc plating sacrifices itself, corroding before the base material, offering added corrosion resistance.