From the inside out - 200g of Primaloft Bio insulation and B-DRY waterproofing - the Sphinx Pull-On is ready for ice-laden mountain towns. Featuring waterproof oiled nubuck, a water-resistant medial zipper, recycled components, and a Vibram Arctic Grip A.T. sole made of Vibram XS Trek. This style runs small. Please order up a half size.