Europe Size 52-53 to US: 2XL
Cross-market adult earmuffs and headbands apparel conversion mapping 52-53 specifications into 2XL.

Analyzing Size Equivalence Across Markets
Europe Size 52-53: Corresponds to a head circumference baseline of 53 (20.9 ) with a Snug / Compact fit type.
US: 2XL: Corresponds to a head circumference baseline of 63.5 (25 ) with a Relaxed / Expanded fit type.