Pirelli P ZERO Nero GT 255/40 R17

Pirelli P ZERO Nero GT is a summer tyre made in total of 46 sizes, ranging from R16 to R16 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 255/40 R17 is 60mm wider than the narrowest dimension (195) and 50mm narrower than the widest one (305). 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.