Under Armour Hundo 1.0 Half Zip Top Armour Stretch - improves mobility and accelerates dry time with lightweight fabrics built in a 4-way stretch. Flatlock Seams - reduce any rubbing or chaffing that regular seams can cause meaning a more comfortable fit all round Anti-Odor Technology - prevents the growth of odor causing microbes. 1/4 Zip design - for easy on/off and on the go ventilation. Droptail - for additional coverage