Carbon steel bar is a general purpose steel with excellent formability and weldability. There are two types of square bars, hot-rolled and cold-rolled.

Carbon steel square bars are used in general purpose structural and mechanical applications such as riveted, bolted or welded bridges and buildings. Used for reinforcing products such as bracing, frames or brackets are also common, carbon steel square rods are also used for general repairs on factory equipment and railings, including decorative ironwork, protective barriers on gates and windows