Suede & 1000 Denier Cordura Upper Our suede upper is legendary for its durability, which we pair with 1000 Denier nylon Cordura for superior protection. GORE-TEX (GTX) 100% waterproof and breathable, GORE-TEX liners ensure that no water gets in, while allowing sweat and moisture to get out. Lace Garage Prevents loose laces from snagging or dragging. At the top of the boot's tongue is a stretch fabric pocket designed to tuck your lace ends into. Vibram® Tanicus Outsole Pentagonal lugs give maximum surface contact for grip in a variety of terrain. How It Fits The 851 last is an update to our popular 850 last. This last fits true to size with an athletic and supportive fit while providing ample room in the toe. Offering a specific heel shape that locks the heel in place for better fit and comfort on the back end of the boot, this supportive fit is ideal for those needing high mileage performance from their gear.