The Callaway Ultrasonic Quilted Technical Pullover with Thermore Thermal Booster is a ¼ zip pullover with 2 tone zippers & elasticated sleeves. Thermore's Thermal Booster has been developed so that the golfer is able to maintain a constant temperature in normal playing conditions. As the temperature drops, this product offers a thermal boost in order that the golfer can maintain a comfortable temperature. This is a unique feature of this technology, allowing the golfer to concentrate on their game instead of the temperature. The product also benefits from dual action Technology which absorbs moisture inside & repels moisture outside.