The Under Armour Women's ColdGear Reactor Vest is a highly rated sleeveless windproof thermal convertible activewear vest available on Amazon. It is made from a blend of polyester and elastane, offering a comfortable and stretchy fit. The vest features ColdGear Reactor insulation, which adapts to your activity level for the right breathability and warmth. The windproof construction helps block out cold air, while the UA Storm technology repels water without sacrificing breathability. The vest has zippered hand pockets and a secure chest pocket for storing essentials. With its innovative technology and performance-driven design, this vest is a top choice for women who want to stay warm and comfortable during outdoor activities.