Sizing Size chart: XS size 0-3 months (newborn) Head circumference - 34cm - 40cm (13.4in - 15.7in) S size 3-6 months Head circumference - 39cm - 45cm (15.4in- 17.7in) M size 6-18 months Head circumference - 44cm - 50cm (17.3in - 19.7in) L size 1.5-8 years Head circumference - 49cm - 54cm (19.3in - 21.3in) Adult size One size for adults
