Bike helmet made of Dual Shell (PVC and ABS). Equipped with 11 vents. Complies with American and European standards for urban bike helmets and European standards for sliding sports. Adjustment system with knob. Size Guide: Small 52.5 to 55 cm Medium 55 to 59 cm Large 59 to 62 cm Bern offers a new version of its iconic bicycle helmet, designed around the strengths that have made it a success, with classic but modern styling, reinforced protection and improved comfort. It will delight you with its sophisticated design. Now lighter (approx 350 g).