Steel Lines And Tubing Are Constructed With Safety And Longevity In Mind. Tubing Is Produced By Wrapping Copper-Coated Steel Around Itself Twice To Form The Tubing. Beveled Seam Edges For Smooth, Head-Free Joint. Double-Wall Tube Provides The Strength And Structural Integrity To Withstand The Extreme Pressures. Provide Excellent Rust And Corrosion Resistance. Used To Fabricate 3/8 Inch Fuel And Transmission Lines.