Our most popular model, the long sleeve tee provides superior cooling when temps are hot, pulls moisture away from the skin, and gives you all day sun protection with it&';s UPF50 rating. DriComfortA(R) GEO 365 mineral infused fabric controls temperature whether it&';s hot our cold, so use it year-round, over a tee, under a vest of jacket, or lounge around the house in comfort. Easy care wrinkle free and won&';t shrink when dried.