Pirelli Night Dragon GT 180/55 R18

Pirelli Night Dragon GT is a summer tyre made in total of 9 sizes, ranging from R15 to R15 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 180/55 R18 is 10mm wider than the narrowest dimension (170) and 20mm narrower than the widest one (200). 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.