SHS and RHS Blue Hollow Section 20 x 20mm (Min.) to 800 x 800mm (Max.) Hollow Section Specification:1) Size: 20 x 20mm (Min.) to 800 x 800mm (Max.)2) Wall thickness: 1.5mm - 40.0mm3) Shape: square, rectangle and special shape4) Surface finish: black, blank, bright and galvanized5) Steel Grade: Q195 - Q235B, ST37-2, ST52, S235, S355, SS400, Fe3606) Conforms to international standards