Columbia Women's Tamiami Sleeveless Shirt Omni-Wick Ripstop 100% polyester Imported Omni-Wick product Omni-Shade UPF 40 sun protection. Antimicrobial treatment protects this product from bacterial growth, vented. Omni-Wick Advanced Evaporation Omni-Shade UPF 40 sun protection Intended to protect the garment from odor Caused by bacteria