The Vizion Reactive 1/2 Zip Tee for Women utilises Thermalite fabric to allow the regulation of your body temperature as you exercise. The combination of Merino wool and Polyester, forms the perfect medium through which wicking can occur, ensuring that you also remain dry. So, as the name suggests the Reactive Running Tee, reacts and adapts to your body, allowing you to run for greater distances without either being slowed down by overheating, or being made uncomfortable by the build up of moisture under your clothing.