Engineered for demanding winter conditions, the Arc'teryx Postour Boot combines waterproof GORE-TEX protection, PrimaLoft(R) insulation, and a versatile removable inner slipper in one highly adaptable system. The insulated slipper delivers standalone comfort around camp or in the lodge, while the outer boot provides premium weather protection and confident grip when the adventure continues. Design: WPN PFC-free treated elastic-yarn textile upper designed for weather protection Integrated collar top cord closure system helps lock in warmth and keep out the elements Removable inner slipper features wool lining, PrimaLoft(R) insulation, and a drop-in PU sockliner In-Shoe Comfort: 300g/sm PrimaLoft(R) insulation in the boot delivers enhanced cold-weather warmth 250g/sm PrimaLoft(R) insulation in the removable inner slipper provides additional insulation Shock-absorbing PU foam base with wool topcloth helps cushion every step Durability & Traction: Foamed TPU mudguards help provide added protection and durability GORE-TEX Invisible Fit membrane offers waterproof protection with a comfortable fit Vibram(R) Arcticgrip compound outsole helps deliver confident traction in winter conditions Additional Details: 7 mm drop 8.5 mm lug depth Drop-in midsole construction Debossed logo detailing