Hankook Kinergy 4S2 H750 is a allround tyre made in total of 81 sizes, ranging from R14 to R14 - this particular dimension is R19, which means it fits to a 19 inch/482.6mm diameter wheel. 245/40 R19 is 90mm wider than the narrowest dimension (155) and 10mm narrower than the widest one (255). 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 R19, there is only one possible speed index for Hankook Kinergy 4S2 H750 - "W", which is good for speeds up to 270 km/h.