Bridgestone Dueler H/T 840 is a summer tyre made in total of 5 sizes, ranging from R15 to R15 - this particular dimension is R16, which means it fits to a 16 inch/406.4mm diameter wheel. This tyre profile of 75 means the sidewall height of the tyre is 75% of the tyre width (245mm), which results in 183.75mm sidewall height. In 245/75 R16, there is only one possible speed index for Bridgestone Dueler H/T 840 - "S", which is good for speeds up to 180 km/h.