I'd be surprised if they put that diffuser in the picture there.
That was an oem option carbon diffuser for facelifts... £300 odd and now discontinued and impossible to find.
You can just get the stock bumper cut... Most people have gone this route.
Also you cant just get an M bumper and fit it.... You'd need to either change your rear lights, or have some serious fettling/ cutting done to get a facelift rear M bumper fit prefaclift rear light profile.... RichardG did this.
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