Europe Size 50 to US: 3-6M

Europe Size 50: Corresponds to a head circumference baseline of 50 $\text{cm}$ (19.7 $\text{in}$) and age range 24–36 $\text{months}$.

US: 3-6M: Corresponds to a head circumference baseline of 41 $\text{cm}$ (16.1 $\text{in}$) and age range 3–6 $\text{months}$.