HSS5-1/2x3/8 (HSS5.5x.375) – HSS Shapes - Round

HSS5-1/2x3/8 is a 5.5 in (140 mm) diameter round hollow section with a 3/8 in (10 mm) nominal wall, weighing 20.55 lb/ft (30.6 kg/m).

Round HSS are closed, circular tube sections, sharing the torsional and biaxial strength advantages of rectangular HSS but in a circular profile that's often preferred where appearance matters — exposed columns, canopy supports, and architectural framing — as well as more utilitarian uses like handrail posts and bollards. The circular shape distributes compressive and torsional loads evenly in every direction, making round HSS a strong, materially efficient choice wherever a round column or post is wanted rather than a square or rectangular one.