FXR Atmosphere Base Layer Long Sleeve Shirt The FXR Atmosphere Base Layers are designed for optimal performance in cool and cold conditions, crafted from a blend of 90 polyester and 10 spandex knit. Their brushed interior enhances comfort and maximizes moisture-wicking efficiency. Featuring tapered cuffs, these base layers minimize bulk for a streamlined fit. Features: 200gsm 90 polyester / 10 spandex knit with brushed interior Moisture-wicking and antimicrobial finish Flat-lock seaming for superior comfort Thumb hole cuffs Tapered cuffs reduce bulk under layers FXR Warmth Rating Max 2