Style no longer sold. Ultra lightweight base layer/exercise long sleeve. Features Stretchy, quick-drying and moisture-wicking polyester and spandex fabric offers very light insulation against skin Odor-resistant fabric treatment helps deter odors Fabric provides UPF 50+ sun protection, shielding skin from harmful ultraviolet rays Offset seams enhance mobility without chafing The men's Patagonia Capilene 1 Silkweight Underwear Long-sleeve Shirt offers a slim fit Technical Specs Best Use: Hiking, running, walking Shirt Type: L/S T-shirt Fabric: 100% polyester Sun-Protective Fabric: Yes Moisture Wicking: Yes Quick Drying: Yes