Firestone Roadhawk 2 is a summer tyre made in total of 56 sizes, ranging from R17 to R17 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 235/55 R17 is 40mm wider than the narrowest dimension (195) and 40mm narrower than the widest one (275). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (235mm), which results in 129.25mm sidewall height. In 235/55 R17, there is only one possible speed index for Firestone Roadhawk 2 - "Y", which is good for speeds up to 300 km/h. In 235/55 R17, Roadhawk 2 usually competes against Turanza 6, which is a tyre from Bridgestone with a rating of 83%, compared to 80% of the Firestone in question.