The DELPHI Master brake cylinder (LM51031) is a professional-grade replacement component engineered for long service life and reliable operation across all conditions your vehicle encounters. The part is built to the following specification: Brake System: AC Delco, Thread Size 1: M10x1, Thread Size 2: M12x1, Piston Diameter [mm]: 22, Aluminium mm. Each dimension is checked against the OEM reference to ensure the component seats and functions correctly first time. Verified to fit OPEL, VAUXHALL 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: 010561, 01-3005580013-A, 03495542, 05-0381 and 34 more. Matching these numbers confirms a like-for-like replacement with no loss of function. DELPHI 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.

Delphi Technologies, with roots dating back to 1994 as part of General Motors, is a globally recognised supplier of fuel injection, ignition, and engine management systems. Delphi specialises in diesel injectors, fuel pumps, ignition coils, lambda sensors, and engine management components. As an OE supplier to major manufacturers worldwide, Delphi products are engineered to original factory specifications. With deep expertise in both petrol and diesel fuel systems, Delphi is the professional's choice for precision engine and fuel system components.