Barum Polaris 3 is a winter tyre made in total of 65 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 100mm wider than the narrowest dimension (135) 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, Polaris 3 usually competes against Radial Champiro WinterPro 2, which is a tyre from GT with a rating of 60%, compared to 0% of the Barum in question.