There is a lot more than a modded fender on this car. Looks like there is also a Hamann front bumper cover with Varis splitters molded in... along with some other customization. See the middle of my bumper on my sig is the same as the one you're asking about. That's the Hamann portion.
The varis splitters molded in are these:
I don't know this as fact or if it's photochopped. I've just stared at a lot of bumpers for the Z4m so that's what it looks like to me.