MMX Performance Coolant Expansion Cap 90mm - BMW MMR03-1502 Audi 8P RS3 Meanwhile a new pressure relief

Meanwhile a new pressure relief valve integrated into the cap always maintains balanced tank pressure

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MMX Performance Coolant Expansion Cap 90mm - BMW MMR03-1502 Audi 8P RS3 Meanwhile a new pressure reliefThe MMX Performance 90mm billet coolant expansion cap for BMWs has been designed from the ground up in the UK, from a solid piece of billet aluminium. Each cap was designed to directly replace the OE cap, not merely stuck in place. Fitment is for models with the matching OE (17 11 7 639 021) part number. Each MMX cap starts life as a solid billet of 6061 aerospace grade aluminium. It's meticulously machined from this billet with the latest CNC 5 axis