Michelin Pilot Sport CUP 2 R 315/30 R20

Michelin Pilot Sport CUP 2 R is a summer tyre made in total of 37 sizes, ranging from R19 to R19 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 315/30 R20 is 30mm wider than the narrowest dimension (285) and 30mm narrower than the widest one (345). This tyre profile of 30 means the sidewall height of the tyre is 30% of the tyre width (315mm), which results in 94.5mm sidewall height.