Bell Span Youth Helmet The Bell Span Youth Helmet offers a modern BMX and skate look and feel for kids to enjoy. The fit is tight and right, with a dial-adjustable fit system that will stay put no matter how rad they get. There are 10 air vents scattered throughout to keep it cool and well ventilated. Staying protected has never been so fun! Features ABS Hard Plastic Shell with EPS Liner Action Fit Sizing How to Measure:With a cloth measuring tape, find your heads circumference just above the ears. Helmet Size Extra Small Small Head Circumference19. 2"-20. 8"49cm-53m20"-21. 9"51cm-55cm | Bell | Span Youth Helmet | Size Small In Matte Black