Bridgestone R249 Ecopia is a summer tyre made in total of 9 sizes, ranging from R22 to R22 - this particular dimension is R22, which means it fits to a 22 inch/558.8mm diameter wheel. 305/70 R22 is 30mm wider than the narrowest dimension (275) and 80mm narrower than the widest one (385). This tyre profile of 70 means the sidewall height of the tyre is 70% of the tyre width (305mm), which results in 213.5mm sidewall height. In 305/70 R22, there is only one possible speed index for Bridgestone R249 Ecopia - "M", which is good for speeds up to km/h.