Continental SportContact 5 SUV is a summer tyre made in total of 93 sizes, ranging from R18 to R18 - 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 40mm narrower than the widest one (295). 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 are 3 possible speed indexes for Continental SportContact 5 SUV - "W","H","V", which are good for speeds up to 270, 210, 240 km/h. In 255/55 R18, SportContact 5 SUV usually competes against Eagle F1 Asymmetric 5, which is a tyre from GoodYear with a rating of 90%, compared to 82% of the Continental in question.