Easy-wearing, ultralight shirt for staying cool in oven-like conditions Extend your fishing days in Simms’ UPF 50 SolarFlex® Crewneck. Built-in COR3™ technology optimizes quick-dry, wicking, and odor-annihilating performance. Flat-seam construction maximizes comfort. Raglan-sleeves promote unrestricted movement. And a crewneck design with a higher backed collar delivers ultimate sun protection. Traditional fit and athletic style come standard.