Ugg Butte Gray Men’s Waterproof Boots Size 13 Brand New Perfect The Butte is the perfect cold weather boot to sport all winter long. Full-grain leather upper features a waterproof and windproof eVent™ membrane that "vents" moisture from inside the shoe for a durably waterproof boot. Fully lined with UGGpure™ with 8mm sherpa lining on vamp and quarter. eVent™ Fabric: Through Direct Venting™ proprietary and patented technology, millions of tiny pores are able to breathe at their full potential, allowing sweat to vent directly to the outside of the fabric in one easy step. Cold-weather rated to -20C" to description. Cushioned EVA footbed and midsole. Durabl Vibram outsole.