Bridgestone Blizzak LM-001 255/50 R20

Bridgestone Blizzak LM-001 is a winter tyre made in total of 147 sizes, ranging from R13 to R13 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 255/50 R20 is 100mm wider than the narrowest dimension (155) and 30mm narrower than the widest one (285). This tyre profile of 50 means the sidewall height of the tyre is 50% of the tyre width (255mm), which results in 127.5mm sidewall height.