TRREX revolutionary performance apparel helps maintain body temperature in extreme conditions or whenever you need it. Through a patent-pending fabric and a special cooling process, TRREX’s cooling ability provides a unique combination of performance, comfort, and convenience. Proven thermal imaging and live military field testing, the shirt can actually adjust core body temperature for up to six (6) hours. We took it to the next level so you can too. So be cool, don’t sweat it, and take the heat off!