A U-Bolt is a U-shaped bolt with two threaded arms from a curved base. U-bolts are useful for attaching pipes to machines, square-shaped U-Bolts are primarily used for lumber applications. Use for cars, trucks, trailers, buses, marinas, farming equipment & agricultural. Comes with 2 hex hi-nuts. Useful for attaching pipes to machines.Square U-shaped bolt with two threaded arms from a curved baseEasy to useThe shape of the letter U with screw threads on both endsComes with 2 hex Hi-nutsPrimarily used for lumber applicationsUse for cars, trucks, trailers, buses, marinas, farming equipment & agricultural.SpecificationsDiameter: 1/2Inside Width: 2-5/8Inside Length: 11-1/2Material: Steel.