Cooper Discoverer STT PRO POR 305/55 R20

Cooper Discoverer STT PRO POR is a summer tyre made in total of 28 sizes, ranging from R16 to R16 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 305/55 R20 is 90mm wider than the narrowest dimension (215) and 0mm narrower than the widest one (305). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (305mm), which results in 167.75mm sidewall height.