Michelin Pilot Sport S 5 245/40 R21

Michelin Pilot Sport S 5 is a summer tyre made in total of 39 sizes, ranging from R19 to R19 - this particular dimension is R21, which means it fits to a 21 inch/533.4mm diameter wheel. 245/40 R21 is 20mm wider than the narrowest dimension (225) and 30mm narrower than the widest one (275). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (245mm), which results in 98mm sidewall height.