Continental UltraContact is a summer tyre made in total of 80 sizes, ranging from R14 to R14 - this particular dimension is R16, which means it fits to a 16 inch/406.4mm diameter wheel. 225/55 R16 is 70mm wider than the narrowest dimension (155) and -30mm narrower than the widest one (195). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (225mm), which results in 123.75mm sidewall height. In 225/55 R16, there is only one possible speed index for Continental UltraContact - "W", which is good for speeds up to 270 km/h. In 225/55 R16, UltraContact usually competes against Primacy 4, which is a tyre from Michelin with a rating of 82%, compared to 0% of the Continental in question.