Falken ZIEX ZE310 Ecorun is a summer tyre made in total of 150 sizes, ranging from R14 to R14 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 245/40 R17 is 60mm wider than the narrowest dimension (185) and -20mm narrower than the widest one (225). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (245mm), which results in 98mm sidewall height. In 245/40 R17, there is only one possible speed index for Falken ZIEX ZE310 Ecorun - "W", which is good for speeds up to 270 km/h. In 245/40 R17, ZIEX ZE310 Ecorun usually competes against Ventus Prime3 K125, which is a tyre from Hankook with a rating of 72%, compared to 81% of the Falken in question.