Kumho Ecsta PS71 is a summer tyre made in total of 172 sizes, ranging from R16 to R16 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 235/50 R18 is 40mm wider than the narrowest dimension (195) and 80mm narrower than the widest one (315). This tyre profile of 50 means the sidewall height of the tyre is 50% of the tyre width (235mm), which results in 117.5mm sidewall height. In 235/50 R18, there are 2 possible speed indexes for Kumho Ecsta PS71 - "V","Y", which are good for speeds up to 240, 300 km/h. In 235/50 R18, Ecsta PS71 usually competes against RainSport 5, which is a tyre from Uniroyal with a rating of 64%, compared to 68% of the Kumho in question.