Pirelli Scorpion Winter is a winter tyre made in total of 213 sizes, ranging from R16 to R16 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 285/40 R20 is 70mm wider than the narrowest dimension (215) and 40mm narrower than the widest one (325). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (285mm), which results in 114mm sidewall height. In 285/40 R20, there are 2 possible speed indexes for Pirelli Scorpion Winter - "W","V", which are good for speeds up to 270, 240 km/h. In 285/40 R20, Scorpion Winter usually competes against Blizzak LM-005, which is a tyre from Bridgestone with a rating of 88%, compared to 0% of the Pirelli in question.