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Exactly, they're all different including models from the same manufacturer so physically trying them on necessary.
They need to fit loose enough for comfort but snug enough that w/ strap fastened, the helmet stays put when shaking your head quickly a few times left/right/left/right also up/down.
Also, don't cheap out as some look Ok but aren't and a good lid-skid important when you need it so best buck up and be safe.
Did you get a Atv/bike/snow machine for Christmas Verne?
~ Pete
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