trimfit Boys' ' Dress Rib Comfortoe 3-Pack 70% Cotton, 26% Nylon, 3% Spandex, 1% Rubber Imported Machine Wash 3-Pairs boys cotton dress rib texture socks Comfort technology Machine wash cold with like colors. Only non-chlorine bleach when needed. Tumble dry low. Do not iron Trimfit. Wear tested and reg since 1921