The Under Armour Women's ColdGear Reactor Vest is a top choice for women who want a sleeveless lightweight vest with advanced insulation technology. It features ColdGear Reactor intelligent insulation that adapts to your activity level, providing the right amount of warmth and breathability. The vest is made from a blend of polyester and elastane, offering a comfortable and stretchy fit. It has a full zip closure and a stand-up collar to keep you protected from the elements. The ColdGear Reactor Vest is also equipped with UA Storm technology, making it water-resistant and suitable for various weather conditions. Whether you're going for a run or running errands, this vest will keep you warm and stylish.