The ultimate T for your hottest training days—it's loose, light, and has vented mesh panels throughout for maximum breathability. Plus, 4-way stretch fabric means you never have to slow down.. Ultra-breathable knit fabric is super lightweight & comfortable. Material wicks sweat & dries really fast. Anti-odor technology prevents the growth of odor-causing microbes. 4-way stretch material moves better in every direction. Underarm gusset provides enhanced mobility, ventilation & chafe-free performance. Dropped, shaped hem for enhanced coverage. Loose: Fuller cut for complete comfort.