Goodyear EfficientGrip SUV 4x4 is a summer tyre made in total of 0 sizes, ranging from R13 to R13 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 285/50 R20 is 285mm wider than the narrowest dimension () and -285mm narrower than the widest one (). This tyre profile of 50 means the sidewall height of the tyre is 50% of the tyre width (285mm), which results in 142.5mm sidewall height.