Vredestein Ultrac Vroti 275/35 R21 103Y

21

21 inches, stands for the diameter of the wheel that the tyre is designed to fit.

R

Radial construction.R stands for radial-ply construction.

103

103 is the load index i.e. the maximum weight each tyre can carry at full speed.

Y

Y is the speed rating i.e. the maximum speed for the tyre at full load.

275

275 is the width in millimetres of the tyres cross section.

35

35 is the Aspect Ratio, it is the ratio of the sidewall height to the cross section width.