Falken Azenis FK510 is a summer tyre made in total of 113 sizes, ranging from R17 to R17 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 215/45 R18 is 10mm wider than the narrowest dimension (205) and 20mm narrower than the widest one (235). This tyre profile of 45 means the sidewall height of the tyre is 45% of the tyre width (215mm), which results in 96.75mm sidewall height. In 215/45 R18, there is only one possible speed index for Falken Azenis FK510 - "Y", which is good for speeds up to 300 km/h. In 215/45 R18, Azenis FK510 usually competes against Ventus S1 evo3 K127, which is a tyre from Hankook with a rating of 81%, compared to 79% of the Falken in question.