Regatta Great Outdoors Childrens/Kids 2 Season Coolmax Trek & Trail Socks Elastane, Polyamide, Polyester The kids Two Season Trek & Trail Sock is constructed with a high Coolmax percentage for exceptional moisture control. Strategic cushioning and reinforced areas prone to wear help keep their feet happy all day long. Cool Max. Elastane (3%), Polyamide (6%), Polyester (28%), Polyacrylic (63%).