Vibram FiveFingers footwear is designed around the foots measurement in inches. There is no real 100 percent translation between your US size and FiveFingers size. In order to find the right size, please measure both feet from heel to tip of longest toe with a ruler in inches. Take the longest measurement of your longest foot and refer to the Vibram FiveFingers mens or womens size chart to find your shoe size. Please click for a video about how Vibram shoes should fit. View the Vibram FiveFingers for your shoe size. View the Vibram FiveFingers for your shoe size. The Vibram FiveFingers Trek Ascent Insulated shoe lets you continue your outdoor adventures even when the weather turns cold. High tenacity nylon, polyester, and wool upper. Built specifically to promote a barefoot-like experience. Ideal for off-road adventures and hiking in all conditions. Upper envelopes the foot to help keep debris out. Speed lace system allows for quick-and-easy adjustments, and accommodates a wider foot or higher instep. 4 mm polyurethane insole with Dri-Lex sock liner featuring antimicrobial technology for a great in-shoe environment. 4 mm EVA midsole provides lightweight cushioning and shock absorption. 4mm Vibram rubber and engineered ICETREK outsole provides exceptional traction on icy surfaces. Machine wash cold, air dry. Imported. Measurements: Weight: 6 oz Product measurements were taken using size 40 (US Womens 8), width B - Medium. Please note that measurements may vary by size. Weight of footwear is based on a single item, not a pair.