Metzeler Roadtec 01 is a summer tyre made in total of 43 sizes, ranging from R16 to R16 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 180/55 R17 is 80mm wider than the narrowest dimension (100) and -60mm narrower than the widest one (120). 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. In 180/55 R17, there is only one possible speed index for Metzeler Roadtec 01 - "W", which is good for speeds up to 270 km/h.
