Under Armour Storm Daytona Half Zip Vest The Under Armour Storm Daytona Half Zip Vest is another a superb gilet from the masters of technical clothing. Featuring their patented Storm technology, the Daytona Vest repels water without sacrificing breathability, and the insulation is paired with lightweight, smooth spacer fabric for the optimum level of warmth. The Under Armour Daytona Half Zip Vest actually adapts to the temperature ensuring you remain warm on cold days and nice and cool when the day starts to heat up.  FEATURES AT A GLANCE UA Storm technology repels water without sacrificing breathability Breathable insulation paired with lightweight, smooth spacer fabric Open hand pockets Reflective details 91% Polyester, 9% Elastane