Michelin Alpin 5 275/40 R20

Michelin Alpin 5 is a winter tyre made in total of 92 sizes, ranging from R15 to R15 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 275/40 R20 is 90mm wider than the narrowest dimension (185) and 40mm narrower than the widest one (315). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (275mm), which results in 110mm sidewall height.