Europe Size 52 to US: 18-24M

Europe Size 52: Corresponds to a head circumference baseline of 52 $\text{cm}$ (20.5 $\text{in}$) and age range 48–84 $\text{months}$.

US: 18-24M: Corresponds to a head circumference baseline of 48 $\text{cm}$ (18.9 $\text{in}$) and age range 18–24 $\text{months}$.