(Head circumference: 52-62 cm) SOFTSHELL DESIGN: The Shield II is a Softshell (in-mold) helmet that has a thin lightweight polycarbonate outer shell that if firmly attached to a shock-absorbing EPS foam core. ERGONOMICAL DESIGN: The ergonomically-shaped Shield II has an interior with removable padding (spare pads included). This helmet is designed to fit head circumferences of 48 - 56cm (18.9  22.0 in) with a small and 52  62 cm (20.5  24.4 in) with a large. SHOCK ABSORBING EPS: In the event of impact, the EPS (expanded Polystyrene) foam core absorbs energy, which progressively buckles upon impact. The outer polycarbonate shell protects the EPS core and helps spread impact energy throughout the entire helmet. ROBUST COMFORT: This helmet weighs 248 grams and features a wing-fit system and rear adjustment dial to provide outstanding comfort to all head sizes within (within the designated head circumferences). I also comes with 4 robust head torch clips. EXCELLENT VENTILATION: This lightweight helmet features an airflow system with large vents allow offers continual air exchange, making this an ideal choice of protection for those long and demanding climbs.