US: 2T-4T to Europe Size 41-43
Cross-market children’s hats, beanies, caps, sun hats, and ear-flap hats apparel conversion mapping 2T-4T specifications into 41-43.

Analyzing Size Equivalence Across Markets
US: 2T-4T: Corresponds to a head circumference baseline of 50 (19.7 ) and age range 24–48 .
Europe Size 41-43: Corresponds to a head circumference baseline of 42.5 (16.7 ) and age range 3–6 .