Pirelli P ZERO 315/35 R21

Pirelli P ZERO is a summer tyre made in total of 332 sizes, ranging from R17 to R17 - this particular dimension is R21, which means it fits to a 21 inch/533.4mm diameter wheel. 315/35 R21 is 110mm wider than the narrowest dimension (205) and 20mm narrower than the widest one (335). This tyre profile of 35 means the sidewall height of the tyre is 35% of the tyre width (315mm), which results in 110.25mm sidewall height.