Continental 4X4 WinterContact is a winter tyre made in total of 18 sizes, ranging from R17 to R17 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 255/55 R18 is 40mm wider than the narrowest dimension (215) and 10mm narrower than the widest one (265). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (255mm), which results in 140.25mm sidewall height. In 255/55 R18, there is only one possible speed index for Continental 4X4 WinterContact - "H", which is good for speeds up to 210 km/h. In 255/55 R18, 4X4 WinterContact usually competes against WinterContact TS 850P SUV, which is a tyre from Continental with a rating of 74%, compared to 0% of the Continental in question.
