Under Armour Men's Fitted Sonic Vented T-Shirt Polyester/Elastane Polyester/Elastane HeatGear Sonic fabric is ultra-soft & smooth for extreme comfort with very little weight VentTM mesh panels deliver true breathability in a light, stretchy, durable, fast-drying fabric Moisture Transport System wicks sweat away from the body Anti-odor technology prevents the growth of odor causing microbes