TRW Master brake cylinder (PMF557) is manufactured to OEM tolerances, ensuring a direct-fit replacement that restores your vehicle to factory specification without any modification. Technical specifications — Thread Size 1: M10x1, Thread Size 2: M10x1, Piston Diameter [mm]: 20, Plastic mm — are verified against the OEM data sheet to guarantee fitment accuracy and performance parity with the original equipment. Compatible with FIAT vehicles; use the vehicle selector above to confirm exact fitment for your make, model, and engine variant. Fitment data is sourced from TecDoc, the authoritative European parts catalogue. This part supersedes original equipment references: 0 204 123 648, 050525, 1020.75, 133079B and 27 more. Matching these numbers confirms a like-for-like replacement with no loss of function. TRW 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 from our UK warehouse with a 30-day money-back guarantee and free hassle-free returns.

TRW Automotive, with roots dating back to 1901 in Cleveland, USA, is a global leader in safety-critical automotive components, now part of ZF Friedrichshafen. TRW specialises in brake pads, brake discs, steering components, suspension parts, and engine valves. As an OE supplier to virtually all major global car manufacturers, TRW products meet the highest safety and performance standards. Trusted by vehicle makers for over a century, TRW delivers braking and steering components that prioritise safety without compromise.