Fresh Foam X midsole foam with approximately 3% bio-based content delivers the most cushioned Fresh Foam experience for incredible comfort; Received the Seal of Acceptance from the American Podiatric Medical Association; Structured yet breathable upper; 6 mm drop; due to variances created during the development and manufacturing processes, all references to 6 mm drop are approximate; Synthetic materials; Weight: 299 grams (10.5 oz)