Kumho Ecsta PS71 is a summer tyre made in total of 137 sizes, ranging from R16 to R16 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 215/40 R17 is 20mm wider than the narrowest dimension (195) and 70mm narrower than the widest one (285). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (215mm), which results in 86mm sidewall height. In 215/40 R17, there is only one possible speed index for Kumho Ecsta PS71 - "Y", which is good for speeds up to 300 km/h. In 215/40 R17, Ecsta PS71 usually competes against Azenis FK510, which is a tyre from Falken with a rating of 71%, compared to 68% of the Kumho in question.