The Under Armour Women's ColdGear Reactor Vest is a high-performance sleeveless windproof thermal vest that is perfect for cold weather workouts. It is made from lightweight and breathable fabric with UA Storm technology, making it windproof and water-resistant. The vest features ColdGear Reactor insulation, which adapts to your activity level for the right breathability and warmth. It has a stand-up collar, zippered hand pockets, and a drop-tail hem for added coverage. The ColdGear Reactor Vest also has a slim and athletic fit, providing a stylish and streamlined look. With its advanced technology and superior comfort, it is no wonder that this vest is one of the most wished-for items on Amazon.