Federal Evoluzion ST-1 255/30 R20

Federal Evoluzion ST-1 is a summer tyre made in total of 61 sizes, ranging from R13 to R13 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 255/30 R20 is 60mm wider than the narrowest dimension (195) and 20mm narrower than the widest one (275). This tyre profile of 30 means the sidewall height of the tyre is 30% of the tyre width (255mm), which results in 76.5mm sidewall height.