Pirelli P ZERO Rosso Direzionale 255/40 R18

Pirelli P ZERO Rosso Direzionale is a summer tyre made in total of 3 sizes, ranging from R18 to R18 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 255/40 R18 is 10mm wider than the narrowest dimension (245) and -30mm narrower than the widest one (225). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (255mm), which results in 102mm sidewall height.