Continental UltraContact is a summer tyre made in total of 80 sizes, ranging from R14 to R14 - this particular dimension is R15, which means it fits to a 15 inch/381mm diameter wheel. 175/65 R15 is 20mm wider than the narrowest dimension (155) and 20mm narrower than the widest one (195). This tyre profile of 65 means the sidewall height of the tyre is 65% of the tyre width (175mm), which results in 113.75mm sidewall height. In 175/65 R15, there are 2 possible speed indexes for Continental UltraContact - "T","H", which are good for speeds up to 190, 210 km/h. In 175/65 R15, UltraContact usually competes against N blue HD Plus, which is a tyre from Nexen with a rating of 42%, compared to 0% of the Continental in question.