SHERPA ADVENTURE GEAR Men's Tsepun Zip Tee 82% Nylon, 18% Polyester Imported Fabric blocks 99% of UV rays (50+ UPF) Quarter-zip style provides superb ventilation and easy on/off with bonded zip chest pocket that secures your essentials Dry-Zone is both a bi-component and a double weave fabric, meaning the interior weave absorbs moisture, while the exterior surface disperses it Woven with anti-bacterial silver ions to minimize odors Raglan sleeves have flat-locked seams to reduce chafing that can occur under pack straps