Ās per thstone: BBS Sport Design II, a $5650 factory option for your Boxster, now painted black by a PO, perhaps to lessen the burden of cleaning those grooves. My own biased opinion
seems shared by others that they are the best looking oem wheels. Even the black looks great, if you keep the silver rim & titanium bolts. They are also, unfortunately, not the lightest oem wheels.
BBS claims the design, but one rep told me they were contracted for Porsche to BBS/Porsche specs and supplied only direct from the manufacturing facility to Porsche for assembly. Which was his way of leading up to the fact that, although they are 2-piece, neither Porsche nor BBS can supply a new rim if yours is damaged.
Laquer seems to have held up well on my rims. And I now have special cleaning tools for the lug bolt recesses and the end of the groove in the "spoke". I can't reach the barrels with the wheels mounted so they ride dirty.