Polarmax Men’s Micro H1 LS Crew with Acclimate AC and Insect Shield is an ultra-innovative high-performance crew built with both Acclimate AC Advanced Cooling and Insect Shield technology. The Acclimate AC, activated by the moisture from your sweat, will keep you significantly cooler to the touch while the Insect Shield will keep any unwanted pesky bugs at bay! Insect Shield will kick any mosquitoes, ticks, ants, flies, chiggers, and midges to the curb! Enhanced with Polarmax Acclimate Dry moisture-wicking/quick drying, Ag47 antimicrobial protection and a UPF Sun Protection rating of 39+. Stay out longer with THE best outdoor adventure shirt around! Relaxed Fitting. Made in the USA!