... arch, sector, triangle, hexagon and octagon, etc Square Hollow Section Pipe/Steel Pipe/Tube 1-Finishing: galvanized,paint, ... rectangle, ellipse, semicircle, arch, sector, triangle, hexagon and octagon, etc 5-Available Diameter 20-600mm or ... : octagon shaped tube, hexagon shaped tube, ellipse shaped tube, arch shaped tube, rectangular shaped tube, square shaped tube, irregalar shaped tube, etc.special ...