BFGoodrich Trail Terrain T/A 245/50 R20

BFGoodrich Trail Terrain T/A is a winter tyre made in total of 48 sizes, ranging from R15 to R15 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 245/50 R20 is 10mm wider than the narrowest dimension (235) and 40mm narrower than the widest one (285). This tyre profile of 50 means the sidewall height of the tyre is 50% of the tyre width (245mm), which results in 122.5mm sidewall height.