K HH LIFA MERINO SET. KIDS. Shell: 57% Merino Wool, 43% Polypropylene. Our warmest kids' base layer set, combining unique Lifa® wicking technology with merino's natural warmth. The best kids' base layer on the market uses a clever 2-layer construction to keep active kids dry and warm. Our Lifa® technology wicks away moisture while merino wool creates breathable insulation. LIFA® MERINO|2-layer construction|Fleece reinforcement on knees and elbows|Elastic waist|Flatlock seams for extra comfort|Raglan sleeve for freedom of movement|Reinforcement fabric on knees|Non-itch fabric|Solution Dyed|ZQ wool