A BOOT FIRST. A SNEAKER SECOND. We didn't get our chops building athletic shoes. We make boots. So when we decided to create a lightweight trainer, we took our 80-plus years of experience and created a boot that acts like a shoe, not a shoe that acts like a boot. We recommend women select 1.5 to 2 full sizes down for correct fit. Nylon. Rubber sole. Shaft measures approximately 8 from arch. SYNTHETIC ULTRALIGHT UPPER For superior weight savings, we source some of the lightest weight synthetic materials with ultra-fast dry times. GORE-TEX (GTX) 100% waterproof and breathable, GORE-TEX liners ensure that no water gets in, while allowing sweat and moisture to get out. ABRASION RESISTANT TOE CAP For added durability, we've added a scuff-proof toe cap to the area that shows the most wear. OPEN CELL POLYURETHANE FOOTBED Our polyurethane footbed provides superior shock absorption with an additional layer of open cell construction for improved air circulation. DANNER TACHYON OUTSOLE 100% rubber for superior abrasion resistance and pentagonal lugs for maximum surface contact.