HeatGear® Sonic fabric is ultra-soft & smooth for extreme comfort with very little weight. Mesh underarm & back panels provide strategic ventilation. 4-way stretch fabrication allows greater mobility & maintains shape. Moisture Transport System wicks sweat away from the body. Anti-odor technology prevents the growth of odor causing microbes. Body: 4.7 oz. Polyester/Elastane. Mesh: 3.5 oz. Polyester/Elastane. Imported.