Optimum use of shell, foam and strap elements ensure comfort and protection. Offers the size and weight advantages of a foam helmet and the durability of a hard shell. Contoured foam crown is expanded polypropylene foam (more durable than polystyrene), channeled for ventilation. Lightweight thermoformed ABS outer shell eliminates gouging yet keeps the helmet dimensions small for superior balance and clearance while climbing. Headband adjusts instantly with a nape-mounted dial, easily operated with one hand. Easy-adjust chinstrap and built-in headlamp clips.