The Under Armour Women's ColdGear Reactor Vest is a versatile and high-performance option for women seeking a sleeveless activewear vest. Made from a blend of polyester and elastane, this vest offers excellent stretch and mobility. It features ColdGear Reactor insulation, which adapts to your activity level to provide the right amount of warmth. The vest also has a full zip front, zippered hand pockets, and a stand-up collar for added convenience. With its innovative technology and stylish design, it's no wonder this vest is a best seller on Amazon.