US: 12-4E to United Kingdom Size 6-AA

US: 12-4E: Corresponds to a foot length of 30.2 $\text{cm}$ (11.89 $\text{in}$), ball width of 12 $\text{cm}$ (4.72 $\text{in}$), acceptable ball width range between 11.7–12.4 $\text{cm}$ (4.61–4.88 $\text{in}$), and fit classification Extra-Wide (12-4E / EEEE).

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).