The Simms Lightweight Baselayer Top adds warmth on its own or can be layered under your favorite jacket. The next-to-skin jersey knit brushed polyester interior provides all day warmth, speed dry moisture wicking and odor control without limiting your range of motion or adding bulk. Featuring flatlock seam construction for the most comfortable fit. Raglan sleevesFlatlock seamsJersey knit brushed polyesterFabric Tech: Body - 192 gsm 92% spun polyester, 8% spandex finished with HeiQ Fresh odor control/HeiQ Speed Dry