Our Stainless Steel Union 6mm (M12x1.0 B) is great for brake and fuel systems. This union features a chrome-plated finish, which provides excellent corrosion resistance. The male and female ends are built to the standard connection sizes, making them fully compatible with most tubing systems. With this union, you can quickly and conveniently join two lines together without having to use any complicated adaptors. Chrome-plated finish for added corrosion resistance. Connection size (M12x1.0 B). Built to SAE standards. Easy to install and will securely join two brake or fuel lines together. Designed for durability and longevity. Can be used in any 6mm line system.