Sumitomo Wt200 is a tyre made in total of 39 sizes, ranging from R13 to R13 - this particular dimension is R15, which means it fits to a 15 inch/381mm diameter wheel. 195/65 R15 is 40mm wider than the narrowest dimension (155) and 30mm narrower than the widest one (225). This tyre profile of 65 means the sidewall height of the tyre is 65% of the tyre width (195mm), which results in 126.75mm sidewall height. In 195/65 R15, there is only one possible speed index for Sumitomo Wt200 - "T", which is good for speeds up to 190 km/h.