ColdGear Reactor is intelligent insulation that adapts to your activity level for the right breathability & warmth for what you’re doing. UA Base 2.0 in sleeves, hood & back is highly versatile mid-weight protection for colder conditions & a variety of activity levels. Front panel uses low-profile insulation sandwiched between two layers of performance fabric for the ultimate mix of warmth & breathability. Low profile hook & loop at center front allows for venting without distractions. Extended cuffs with thumb loop add extra protection. Secure zip hand & chest pockets. Adjustable hem.