Genuine OEM Audi Rear Brake Caliper Retaining Spring, part number 5WA615269. This spring is designed to securely hold the brake caliper components in their correct positions within the rear brake assembly. It plays a vital role in preventing brake pad rattling and ensuring consistent contact with the brake rotor for effective braking. Constructed from durable metal wire, it weighs approximately 0.0133 kg and measures 13 cm in length. Using a genuine OEM retaining spring guarantees the correct tension, material strength, and corrosion resistance, which are critical for reliable and safe braking performance.