Goodyear EfficientGrip SUV 4x4 is a summer tyre made in total of 0 sizes, ranging from R13 to R13 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 275/65 R18 is 275mm wider than the narrowest dimension () and -275mm narrower than the widest one (). This tyre profile of 65 means the sidewall height of the tyre is 65% of the tyre width (275mm), which results in 178.75mm sidewall height.