About this item Durable & impact-resistant material With robust and durable PVC and PC, EPS foam, it absorbs impact and protects the head in the event of a crash All-round breathable and lightweight With 18 ventilation openings, the women's bicycle helmet allows air to pass through and stays cool. The breathable lightweight material is comfortable to wear. Adjustable head circumference & quick release RaMokey bicycle helmets for adults can be used on different head sizes.