The PFG ZERO Rules Polo Shirt sports Columbia's industry-leading super-cooling technology to keep you cool during dynamic activity in the heat. Soft, lightweight 100% polyester ZERO interlock fabric is treated with an antimicrobial finish to help reduce odors, so you stay fresher longer. Omni-Freeze ZERO technology reacts with your sweat to lower the temperature of the material, while Omni-Shade UPF 30 sun protection helps shield your skin against harmful UV rays. Omni-Wick technology pulls moisture away from the skin for quick evaporation, ensuring that you stay comfortably dry. The rib-knit collar provides a snug, but not-too-tight fit. Modern Classic fit. Imported.