Sidewall inscription

A short explanation is given below of the elements which make up the complete tyre designation and the significance of the individual numbers and letters.

What does 205/55 R 16 W actually mean?
205 - Tyre width in millimetres
55 - Height of the sidewall shown as a percentage of the tyre width i.e. 55% of 205 mm
R - Code for the tyre contsruction (R = Radial tyre)
16 - Rim diameter in inches
W - Symbol for the approved maximum speed (V = up to 150 mph, W = up to 168 mph, ZR within the size designation = over 150 mph)

Other designations:
rf - reinforced e.g. 205/55 R16 W rf
RF – run flat tyre e.g. 205/55 RF16 W
XL - Extra Load (designates specially reinforced tyres)
M + S - For winter tyres e.g. 205/55 R16 W M+S