US: 11-6E to United Kingdom Size 9-D

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 9-D: Corresponds to a foot length of 27.2 $\text{cm}$ (10.71 $\text{in}$), ball width of 10.4 $\text{cm}$ (4.09 $\text{in}$), acceptable ball width range between 10.1–10.7 $\text{cm}$ (3.98–4.21 $\text{in}$), and fit classification Standard Width (10-D / M).