Continental ContiWinterContact TS 850P is a winter 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. 275/40 R18 is 275mm wider than the narrowest dimension () and -275mm narrower than the widest one (). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (275mm), which results in 110mm sidewall height.