Falken EuroWinter HS01 is a winter tyre made in total of 359 sizes, ranging from R13 to R13 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 225/75 R17.5 is 70mm wider than the narrowest dimension (155) and 90mm narrower than the widest one (315). This tyre profile of 75 means the sidewall height of the tyre is 75% of the tyre width (225mm), which results in 168.75mm sidewall height. In 225/75 R17.5, there is only one possible speed index for Falken EuroWinter HS01 - "", which is good for speeds up to km/h.
