The steel brake line tubes are used as a common automotive tubing for hydraulic brake, fuel, transmission cooling, and power steering lines.
The basic tubes are copper brazed steel tubes, made to general automotive standard specifications like SAE J527, ASTM A254. They are further treated by zinc plating (galvanizing), GALFAN coating, PVF coating, aluminum-rich epoxy coating, and nylon coating for enhanced protection against corrosion.
The final tubes meet major industrial standards like JASO M101, GM123M/124M etc., and the are strictly tested because they must be in good condition to ensure the safety driving of vehicles on and off road.