| SIZE | FRAME LENGHT | TYPE OF FACE (European type) | |
| XS: | 130mm | For a very small face | |
| S: | 135mm | For standard female face or small male face | |
| M: | 140mm | For medium to large women or rather standard men | |
| L: | 145mm | For women with a very large face or men with a rather large face | |
| XL: | 150mm | For very large face women or very large face men |
These dimensions are for guidance only and for European face types. Standards can vary greatly from one country or region to another.