The perfect combination of Merino and LIFA® make these base layers durable and warm.Our warmest base layers, LIFA® Merino is a staple with professional athletes and a favorite with kids.Unmatched durability makes these thermals perfect for active kids who play hard.This base layer set is solution dyed for less water waste and the wool is certified by ZQ.-a third party audited wool standard that requires growers to adhere to the best farm management practices.Composition:Shell:57% Merino Wool, 43% Polypropylene. Compare prices from: Helly Hansen in Baby & Children's Clothing