Cooper Discoverer STT PRO 255/75 R17

Cooper Discoverer STT PRO is a tyre made in total of 46 sizes, ranging from R13 to R13 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 255/75 R17 is 224mm wider than the narrowest dimension (31) and 50mm narrower than the widest one (305). This tyre profile of 75 means the sidewall height of the tyre is 75% of the tyre width (255mm), which results in 191.25mm sidewall height.