Style 4174 Semi-fitted Heat Release Technology actively pulls heat away from the skin to help stop sweat before it starts Breathable cotton stretch feels soft, airy, and moves with you Staycool+ technology wicks sweat to help keep you cool and dry​ Keep cool and help stop sweat before it starts with the Jockey Cool Cotton Stretch Crew Neck Undershirt. Thanks to Heat Release technology, this soft, stretchy layer delivers cooling comfort under your favorite shirts and sweaters.