Pirelli WINTER SOTTOZERO Serie III 285/30 R21

Pirelli WINTER SOTTOZERO Serie III is a winter tyre made in total of 228 sizes, ranging from R16 to R16 - this particular dimension is R21, which means it fits to a 21 inch/533.4mm diameter wheel. 285/30 R21 is 80mm wider than the narrowest dimension (205) and 30mm narrower than the widest one (315). This tyre profile of 30 means the sidewall height of the tyre is 30% of the tyre width (285mm), which results in 85.5mm sidewall height.