The Under Armour Women's ColdGear Reactor Vest is a top-rated activewear vest that is perfect for cold weather workouts. It is made from a blend of polyester and elastane, providing a comfortable and stretchy fit. The vest features ColdGear Reactor insulation, which adapts to your activity level to provide the right amount of warmth. It also has a quilted design and a stand collar for added style and protection. With its moisture-wicking properties and lightweight construction, this vest is ideal for layering during outdoor activities.