Bought these for my son when he was learning to use roller blades. They are comfortable and can fit many sizes. I wouldn't get them for kids under 50lbs because they can only get so small, and i think at 50lbs these wouldn't sag and you could get them to fit snug enough. These would be too big for my 4yo who is only 35 lbs. My son says they're comfy and overall we're very happy with this purchase.