This is our second pair a year later! Waterproof and toasty — we put our Little in wool socks and these boots, and her toes were still toasty after a couple of hours in the snow (≈28°F). It's really lightweight, too, so kids don't tire out as quickly!I think they run a little big. Last year she wore size 10 shoes but was fine in size 9 boots + thick wool socks. This year, she wears an 11 in real shoes but could still cram her foot and sock into the size 9 boots. She said it was a little tight but then proceeded to play for hours without problem. She’s now outgrowing size 11 (real shoes) but size 10 boots + socks are more than ample.ETA - great as hand-me-downs... our subsequent Littles have had just as good experience with these even after being worn by an older sibling. It should be noted that we only get a few snows a year, so not heavy use.....