adidas hat size chart

Size Length (Inch) Length (cm)
Children (OSFC) 19.7" - 20.5" 50 - 52
Youth (OSFY) 20.5" - 21.3" 52 - 54
Women (OSFW) 21.3" - 22.0" 54 - 56
Men(OSFM) 22.0" - 22.8" 56 - 58