"Outdoorsmen will find an activewear favorite in the Columbia Zero Rules Light-Weight Crew-Neck Short-Sleeve Shirt. Omni-Shade UPF 50 sun protection makes this lightweight shirt an excellent choice for summer adventures. So does Omni-Freeze Zero, a sweat-activated super-cooling technology that accelerates wicking and moisture absorption to enhance evaporation while lowering fabric temperature. The Columbia Zero Rules Light-Weight short-sleeve crewneck shirt also features Omni-WICK side panels for enhanced warm-weather comfort. 52% recycled polyester/48% polyester. Center Back Length: 29"". Machine wash. Imported.Manufacturer style #: 2118501. 52% recycled polyester/48% polyester Omni-Shade UPF 50 sun protection Omni-Freeze Zero sweat-activated super-cooling technology Omni-WICK side panels"