Vredestein ULTRAC 255/40 R21

Vredestein ULTRAC is a summer tyre made in total of 83 sizes, ranging from R15 to R15 - this particular dimension is R21, which means it fits to a 21 inch/533.4mm diameter wheel. 255/40 R21 is 80mm wider than the narrowest dimension (175) and 40mm narrower than the widest one (295). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (255mm), which results in 102mm sidewall height.