275/35 R20 doesn't belong to the most popular dimensions for tyres - there are tyre models available, which can be compared to 325/30 R21, 155/60 R15, 155/65 R13. Let's break down the sizing - 35 is height of the tyre, which is calculated as 35% of the tyre width (275mm), which means the sidewall height has 96.25 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 255/45 R20(2316.92 mm), 185/75 R16(2148.54 mm), 255/65 R16(2318.18 mm), 195/50 R16(1889.35 mm), 265/30 R22(2255.04 mm), 195/65 R15(1993.34 mm), 265/40 R20(2261.95 mm). You can find 275/35 R20 on 7 car models - mainly Ferrari, Audi, BMW.