General Altimax Winter 3 is a winter tyre made in total of 36 sizes, ranging from R13 to R13 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 235/55 R18 is 80mm wider than the narrowest dimension (155) and 10mm narrower than the widest one (245). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (235mm), which results in 129.25mm sidewall height. In 235/55 R18, Altimax Winter 3 usually competes against N blue HD Plus, which is a tyre from Nexen with a rating of 42%, compared to 43% of the General in question.