A circle steel bar, also known as a round bar, is a long, cylindrical metal bar with a circular cross-section. It is made from a variety of materials, including carbon steel, stainless steel, and alloy steel.

Circle steel bars are commonly used in construction and engineering applications, such as in the manufacture of machinery, equipment, and components. They are also used in the manufacturing of automotive parts, industrial equipment, and in the construction of infrastructure. Circle steel bars can be cut, shaped, and welded to create a variety of products, including furniture, sculptures, and decorative items.