Get a helmet with HECC certification and a full face shield or cage.
Youth hockey rules require a face cage for any player under 18; most adult leagues don't require one. Some beginner hockey leagues do, though. When you try the helmet on, make sure that the wires of the cage aren't across your field of vision.
SizingHelmets come in youth and adult sizes. To fit a helmet, loosen the adjustment screws, put it on your head and gently squeeze helmet together until its snug, then tighten screws (a friend or parent will come in handy). When the helmet is on you head if you try to wiggle it with your hands it should move the skin on your head. front of helmet should be just above your eye brows and just below the occipital bone at the back of your head. Don't forget a faceshield, either wire or plastic.

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