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Width designators
Some systems also include the width of a foot. There are different methods indicating the width:
The measured width is indicated in millimetres (mm). This is done with the Mondopoint system.
The measured width is assigned a letter (or combination of letters), which is taken from a table (indexed to length and width) or just assigned on an ad-hoc basis: Examples include (each starting with the narrowest width):
A, B, C, D, E, EE, EEE, EEEE, F, G (typical North American system)