Imperial F110 is a summer tyre made in total of 12 sizes, ranging from R20 to R20 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 275/45 R20 is 10mm wider than the narrowest dimension (265) and 30mm narrower than the widest one (305). This tyre profile of 45 means the sidewall height of the tyre is 45% of the tyre width (275mm), which results in 123.75mm sidewall height. In 275/45 R20, there are 2 possible speed indexes for Imperial F110 - "V","W", which are good for speeds up to 240, 270 km/h. In 275/45 R20, F110 usually competes against PremiumContact 6, which is a tyre from Continental with a rating of 78%, compared to 0% of the Imperial in question.