Smartwool Kids' Hike Light Crew 58% Merino Wool, 39% Nylon, 3% Elastane Knit in the USA Designed to fit perfectly in kids' shoes without additional bulk. Sizing clearly indicated on the sock Flat knit toe seam Elasticized arch brace Machine Wash Warm, Wash Inside Out. Wash With Similar Color. Do Not Bleach, Tumble Dry Low, Do Not Iron, Do Not Dry Clean.