United Kingdom Size 30 to US: 34

United Kingdom Size 30: Corresponds to a waist size of 75 $\text{cm}$ (30 $\text{in}$), total strap length of 90 $\text{cm}$ (35.4 $\text{in}$), and recommended fit classification Standard / Regular.

US: 34: Corresponds to a waist size of 85 $\text{cm}$ (34 $\text{in}$), total strap length of 100 $\text{cm}$ (39.4 $\text{in}$), and recommended fit classification Standard / Regular.