The MMX Performance billet oil filler cap for BMW S58 and B48E engines has been designed from the ground up in the UK, from a solid piece of billet aluminium. Each cap is designed to directly replace the OE cap, not merely stuck in place.
Please check the underside of your factory oil cap for the OE part number. The MMX billet oil cap for the S58 and B48E fits OE part number 11 12 8 654 637.
This part also goes by the following cross reference.
Cross Reference Part Number: