Round bar
The default for balusters and vertical infill — comfortable to handle, easy to weld into curved or angled runs, the most commonly ordered section.
Square bar
Common in gate frames and more contemporary railing designs where a crisper, more geometric line is wanted over round bar's softer profile.
Flat bar
Used structurally (brackets, reinforcement) and decoratively (borders, trim details) — less common as the primary visible element, more common as a supporting component.
Sizing
Bar diameter/section size is driven by both look (thinner bars read as more delicate, thicker as more substantial/secure-feeling) and structural role (a newel post needs a heavier section than a regular baluster). We size these against your specific run, not off a fixed catalogue number.
See our bars, rods & sections page for what we currently trade.