Avon ZV7 is a summer tyre made in total of 441 sizes, ranging from R13 to R13 - this particular dimension is R19, which means it fits to a 19 inch/482.6mm diameter wheel. 225/40 R19 is 135mm wider than the narrowest dimension (90) and -95mm narrower than the widest one (130). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (225mm), which results in 90mm sidewall height. In 225/40 R19, there is only one possible speed index for Avon ZV7 - "Y", which is good for speeds up to 300 km/h.