Hankook Ventus S1 evo3 K127 is a summer tyre made in total of 109 sizes, ranging from R17 to R17 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 245/40 R18 is 40mm wider than the narrowest dimension (205) and 40mm narrower than the widest one (285). 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 R18, there is only one possible speed index for Hankook Ventus S1 evo3 K127 - "Y", which is good for speeds up to 300 km/h. In 245/40 R18, Ventus S1 evo3 K127 usually competes against Azenis FK510, which is a tyre from Falken with a rating of 79%, compared to 82% of the Hankook in question.