The Under Armour Women's ColdGear Reactor Vest is a popular choice among women looking for a sleeveless insulated lightweight safety activewear vest. Made with a blend of polyester and elastane, this vest offers excellent insulation and flexibility. It features a zippered closure and a stand-up collar to keep you warm and protected from the cold. The vest also includes reflective details for enhanced visibility during outdoor activities. With its innovative ColdGear Reactor technology and stylish design, the Under Armour Women's ColdGear Reactor Vest is a top-selling option on Amazon.