Meet HeatGear Sonic: UA’s newest and greatest baselayer innovation. We started the “performance” revolution with our original HeatGear compression—the ultra-tight fit that increases muscle power…and makes you feel invincible. This latest UA fabric wears like a second skin so you get the same powerful compression, plus extreme comfort for all-day wear. THE FUNDAMENTALS: COMPRESSION: This ultra-tight, second-skin fit delivers a locked-in feel that keeps your muscles fresh & your recovery time fast. Smooth fabric provides extreme comfort and compression without restriction. 4-Way Stretch fabrication allows greater mobility and maintains shape. Signature Moisture Transport System wicks sweat away from the body. Anti-Odor technology prevents the growth of odor causing microbes. Smooth, chafe-free flatlock seam construction. 6" inseam. Polyester/Elastane.