Streamline® copper solder joint Fittings for supply/pressurized systems have been the leading brand of copper fittings for over 80 years. Available in both wrot copper and cast bronze, our product selection has grown to become the most extensive in the industry. We are the acknowledged experts at engineering and manufacturing precision solder joint copper fittings. Quality, consistency and reliability have made the Streamline® brand trusted and specified all around the world.