Tri-Mil‘s raw steel finished J-Tube is designed as an aftermarket replacement for the heater boxes. Made with 5/16″ thick flanges and uses 1-3/8″ diameter 16 gauge mild steel tubing that is mandrel bent, mig welded and test fit to ensure optimum quality and performance. To enhance longevity it is suggested to clean and paint your new J-Tubes with a high heat coating. We have found that a BBQ paint works well! Fits the VW Type 3. Sold as pair.