US: XS (32–34) to United Kingdom Size 38–40

US: XS (32–34): Corresponds to a chest width of 81.3–86.4 $\text{cm}$ (32–34 $\text{in}$), neck collar girth of 35.6 $\text{cm}$ (14 $\text{in}$), sleeve length of 81.3 $\text{cm}$ (32 $\text{in}$), and fit style Slim Tailored Fit.

United Kingdom Size 38–40: Corresponds to a chest width of 96.5–101.6 $\text{cm}$ (38–40 $\text{in}$), neck collar girth of 39.4 $\text{cm}$ (15.5 $\text{in}$), sleeve length of 86.4 $\text{cm}$ (34 $\text{in}$), and fit style Classic Regular Fit.