Structural Tubes Round Pipes Galvanized Pipes & Tubes Mechanical & Ornamental Tubes     A500 B STRUCTURAL TUBE Square sizes 2" x 2" thru 12" x 12" Rectangle Sizes 3" x 2" thru 12" x 8" Thickness 0.120" thru .625" Lengths 20' 25' 30' 35' 40' and 48'