Michelin Pilot Sport CUP 2 R is a summer tyre made in total of 17 sizes, ranging from R19 to R19 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. This tyre profile of 30 means the sidewall height of the tyre is 30% of the tyre width (275mm), which results in 82.5mm sidewall height. In 275/30 R20, there is only one possible speed index for Michelin Pilot Sport CUP 2 R - "Y", which is good for speeds up to 300 km/h.