The Turtle Fur Comfort Shell Solid Shellaclava splits the job in two: a single-layer hood keeps a kid's head breathable under a helmet, while a separate double-layer neck section adds extra warmth exactly where cold air sneaks in. The bottom tucks into a jacket's collar, so snow and wind stay out instead of working their way down the back. Comfort Shell(TM) fabric wicks moisture and resists odor, so the hood stays comfortable through a full day of active play. What Our Gearhead(R) Experts Are Saying:"My kid wore this under a helmet all day on a windy lift and never complained about overheating, but the second we stopped for lunch outside, that extra neck layer kept them from shivering while we ate. I didn't have to choose between breathable and warm."