Genuine OEM Jaguar Brake Line Copper Washer, part number C2C31805. This small but critical component is designed to create a secure, leak-proof seal for various connections within the brake fluid system. It functions as a gasket, preventing fluid leaks and maintaining system pressure. Made from soft copper, it deforms slightly upon tightening to form a perfect seal. Weighing only 0.01 kg, it is essential for proper brake function. Using a genuine OEM copper washer ensures the correct material composition and dimensions for a reliable seal, which is paramount for brake system safety and performance.