FIT WITH FLAT LOCK SEAMS AND LIGHTWEIGHT FABRIC TO KEEP YOU WARM WITHOUT RESTRICTING MOTION. HH LIFA® Light is a performance thermal underwear, delivering light weight insualtion and comfort for everyday use and high performance activities. HH LIFA® light constructed with 100% Lifa fiber is quick-dry, very breathable and super lightweight. Continually perfected over the last 40 years, Lifa® Stay Warm technology is the unique ingredient of all Helly Hansen base layers. Features: Light weight insulation  Flat lock seams  Fitted  125g/m2