Goodyear EfficientGrip SUV 4x4 is a summer tyre made in total of 0 sizes, ranging from R to R - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 275/55 R20 is 275mm wider than the narrowest dimension () and -275mm narrower than the widest one (). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (275mm), which results in 151.25mm sidewall height.