Quote from Black Diamond's web site:
"You already know that a helmet is a must. But what you may not know is what kind of helmet? A traditional hardshell to protect your noggin from rock fall? A foam number thatâ€™s got an excellent ventilation system? Well, weâ€™ve made this difficult choice easy for you with the Hemisphere. As a â€œhybridâ€? helmet, that spans the gap between foam and hardshell and delivers the benefits of both, the Hemisphere is ultra durable and totally comfortable. The Hemisphere is constructed with EPS foam and a polycarbonate shell. Weâ€™ve wrapped the polycarbonate around the lower edge at the helmet to increase the durability. PLUS, this helmetâ€™s got an incredible ventilation system to keep you cool and a modern design thatâ€™s both functional and looks great."
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