Troxel Spirit Riding helmet size small Features: Low profile Full coverage design for optimal comfort Maximum airflow vent placement FlexVisor DialFit System Extensive size range, including XS for young riders FlipFold removable and washable headliner with Air-Channel technology ASTM/SEI-certified Sizing (Hat Size) XS (6 1/4 - 6 1/2) S (6 1/2 - 6 7/8) M (7 - 7 3/8) L (7 3/8 - 7 3/4)