Bridgestone Battlax S21 180/55 R17

Bridgestone Battlax S21 is a summer tyre made in total of 10 sizes, ranging from R17 to R17 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 180/55 R17 is 30mm wider than the narrowest dimension (150) and 20mm narrower than the widest one (200). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (180mm), which results in 99mm sidewall height.