Vivobarefoot Primus Sport IV Preschool StoneFrom the playground to weekend adventures, the Vivobarefoot Primus Sport IV Preschool Stone is built to keep busy little feet moving naturally. Lightweight, flexible and foot shaped, these barefoot trainers help kids build strength, balance and coordination with every step. Natural Movement for Growing Feet Designed around Vivobarefoots foot shaped, zero drop concept, the Primus Sport IV Preschool Stone lets kids run, jump and climb with natural