U-J Bend Specifications ----------------------Tube Diameter 3.5" O.D. U-Bend Centerline Radius 6" Approx. Leg Length 11" Tube Thickness .65" (1.65mm) Vibrant's unique U-J Mandrel Bent Tubing combines a 18 degree bend and a 45 degree bend into one integral unit to give fabricators the ability to get up to 3 seperate bends and a substantial straight length from each piece. Ideal for building custom exhaust systems, headers, downpipes, intercooler piping, etc.... Aluminized Mild Steel is a superior grade of Mild Steel. To be classified as Aluminized Steel, cold rolled metal sheet is hot-dip coated with an aluminum-silicon alloy. This process allows the steel to be far more resistant to corrosion and heat than normal mild steel.