4F M248 Navy Blue Seamless Underwear for Boys 4FJWAW25USEAM248 31S 4F underwear for boys provides high thermal insulation properties and thermal comfort both during long hours spent on the slopes and your favorite everyday activities on cold days. Technical data: Main material: 95% polyamide, 5% elastane Cut: compression that fits tightly to the body Standard hip-length T-shirt cut Raglan sleeves Mid-rise leggings with long legs Made of synthetic material that ensures durability and is easy to care for Seamless construction, perfect as a first layer Thermoactive - maintains optimal body temperature Quick-drying finish - moisture wicking and freshness Round neckline 4FSkin technology ensures a perfect fit and freedom of movement Set: top + bottom