Keep your core warm in the Nike Therma-FIT Vest. The perfect layer for cold days on the field, this vest features Nike Therma-FIT technology that helps you stay warm. Soft fabric and a 1/2-length zipper add the finishing touches to this sideline essential. Customize the colors for a look that's right for your team. Nike Therma-FIT technology helps manage your body?s natural heat to help keep you warm in cold-weather conditions. A half-length zipper allows you to cool down or zip up as the weather changes. 100% Polyester.