285/35 R20 doesn't belong to the most popular dimensions for winter tyres - there are 16 tyre models available, which can be compared to 195/50 R15, 165/65 R14, 190/55 R17. Let's break down the sizing - 35 is height of the tyre, which is calculated as 35% of the tyre width (285mm), which means the sidewall height has 99.75 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is 2222.68 mm, which is very similar to 215/70 R16(2222.36 mm), 205/55 R19(2224.56 mm), 245/35 R21(2214.51 mm), 275/45 R18(2213.88 mm), 225/55 R18(2213.88 mm), 285/30 R21(2212.94 mm), 285/40 R19(2232.42 mm). There are multiple speed indexes available for winter tyres in 285/35 R20: V(240km/h), W(270km/h). The same goes for weight indexes: 100, 104.