The Under Armour Women's ColdGear Armour Compression Mock is a top-selling turtleneck activewear vest on Amazon. It is designed to keep you warm and comfortable during your workouts. The compression fit provides a snug and supportive feel, while the ColdGear fabric traps heat to keep you warm in cold weather. The mock neck design offers extra coverage and protection against the elements. This vest is perfect for layering under other activewear or wearing on its own. It is available in a variety of colors and sizes to suit your style and fit preferences.