I bought these glasses for my son (11), as I have read in other reviews that it fails relatively small. I find that they actually normal, just like a sports glasses, fails. I have a normal-sized head and it fits me well.
My son it fits perfectly and she loves the stylish appearance. Is just not a typical children's glasses and for the price a real snapper.
He carries especially when skiing and it's important that the UV and UVA protection 400 is present.
Particularly pleasant it is that the straps fit snugly on the head (but do not go behind the ears), and stay clear of ski helmet. The spectacle is firmly seated on the head, but not too tight so that the glasses do not fog up permanently.
So far, my son is always driven with a typical ski goggles, but after a certain age you just want a genuine sunglasses ;-). Since we were not sure but if he really get along with a pair of sunglasses while skiing, we did not buy the same super-duper luxury model and therefore end up in the X-LOOP.
The attempt was successful in any case. He loves this sport glasses and transmits them as often as possible. We have equal bought another 2 glasses in a different color combination, since the price-quality ratio is unbeatable in our eyes.