Sourced from HELLA, this master brake cylinder (8AM 355 503-581) combines precision engineering with durable materials to meet the demands of everyday driving and extended service intervals. Technical specifications — Bore Diameter [mm]: 24 mm, Connecting thread: M10 x 1 (x2), Material: Polyurethane, Brake System: TRW — are verified against the OEM data sheet to guarantee fitment accuracy and performance parity with the original equipment. Verified to fit AUDI models. All compatibility data is cross-checked against the TecDoc database — select your vehicle to confirm the part matches your specific engine and year. This part supersedes original equipment references: 010384, 050259, 0 986 480 832, 102321 and 41 more. Matching these numbers confirms a like-for-like replacement with no loss of function. HELLA is a recognised supplier of automotive braking components to independent workshops and dealer networks across Europe. All parts are sourced from authorised distribution channels and carry full manufacturer traceability — you receive exactly the same component supplied to professional garages and dealer workshops. If fitment or specifications do not match your vehicle, our technical team can help identify the correct alternative — use the vehicle selector or contact us with your VIN for a guaranteed-fit recommendation. Replacing worn components on schedule preserves your vehicle's safety, reliability, and resale value — and aftermarket parts from established brands deliver OEM-equivalent performance at a fraction of the dealer price. Every part is dispatched with tracked delivery and a 14-day money-back guarantee with hassle-free returns.

HELLA, founded in 1899 in Lippstadt, Germany, is a global automotive lighting and electronics specialist now operating as FORVIA HELLA. HELLA specialises in headlamps, rear lights, signal lighting, sensors, actuators, and electronic control units. As an OE supplier to virtually all major car manufacturers, HELLA products represent the cutting edge of automotive lighting and electronic technology. With 125+ years of innovation in vehicle illumination and electronics, HELLA is the definitive choice for high-quality lighting and electronic component replacements.