1/8" Natural wool shoe inserts!! Buy for existing pairs big Kid pairs or add to a new order!! Will make feet cozy in winter and if shoes are fitting a little looser will help take up some space then take them out when gets warmer out. If buying to add to new pair ,3/8”" or little less bigger then foot should still be good unless wearing with thick socks or wide feet may want to add a little bit more. If need a replacement for adult pair or big kids specify size