The warmest foundational layer for winter’s coldest most extreme conditions refined with an ultra-high collar additional odorControl and a highly elastic wool blend for body-mapping insulation. Merino wool and a highly elastic highly insulating synthetic blend provide the most insulation of any of our skin layers with an updated neck-warmer collar construction that extends the protection. The ultrasoft textile doesn’t irritate like wool and its high elasticity means it also doesn’t lose its shape when it stretches. Instead it moves with your body maintaining a low-volume next-to-skin fit to trap warmth and expel moisture – both of which are critical for comfort in deep winter. Composition BODY 50%PP 31%WO 10%PA 6%EA 3%CF; NECK 91%PP 6%EA 3%CF The finer details FEATURED FABRICSOur warmest skin layer textile an ultrabreathable ultrasoft blend that incorporates carbon fiber to provide permanent odorControl properties. Synthetic materials grant high stretch-and-return while wool adds antimicrobial properties and natural thermoregulation. CONSTRUCTION/FITA second-skin fit keeps the textile against your body maximizing thermoregulating properties and push-pull moisture management for a warm dry microclimate. Single-piece construction eliminates seams and friction. ENGINEERINGodorControl: The Ultraz model incorporates higher carbon content and the natural antimicrobial properties of merino wool for permanent odorControl.