Michelin Pilot Sport EV is a summer tyre made in total of 89 sizes, ranging from R19 to R19 - this particular dimension is R19, which means it fits to a 19 inch/482.6mm diameter wheel. 235/45 R19 is 10mm wider than the narrowest dimension (225) and 80mm narrower than the widest one (315). This tyre profile of 45 means the sidewall height of the tyre is 45% of the tyre width (235mm), which results in 105.75mm sidewall height. In 235/45 R19, there are 2 possible speed indexes for Michelin Pilot Sport EV - "W","Y", which are good for speeds up to 270, 300 km/h.