US: 11-6E to United Kingdom Size 6-AA

US: 11-6E: Corresponds to a foot length of 31.2 $\text{cm}$ (12.3 $\text{in}$), ball width of 12.4 $\text{cm}$ (4.88 $\text{in}$), acceptable ball width range between 12.1–13 $\text{cm}$ (4.75–5.1 $\text{in}$), and fit classification Ultra-Wide (11-6E).

United Kingdom Size 6-AA: Corresponds to a foot length of 23.8 $\text{cm}$ (9.35 $\text{in}$), ball width of 9 $\text{cm}$ (3.5 $\text{in}$), acceptable ball width range between 8.8–9.2 $\text{cm}$ (3.45–3.6 $\text{in}$), and fit classification Extra Narrow (7-3A / AAAA).