Running shoe built for the neutral to under-pronator who requires an enhanced cushioning and extended durability. The MudClaw 330 'O' is an extremely durable and aggressively outsoled fell/ hill/ mountain or orienteering shoe. Synthetic upper has a dual layer mesh for comfort and protection. Molded midsole cushioning. Outsole uses inov-8 sticky rubber compound that optimizes grip in wet conditions. Meta-flex: Incorporates a groove which is anatomically aligned in front of the metatarsal heads to provide a natural fore foot flex. Meta-shank: New 5-finger meta-shank aligns with each individual metatarsal for greater flexibility when contouring while retaining underfoot impact protection. Met-cradle: The upper webbing support is anatomically positioned to cradle the fore foot behind the metatarsal heads and provide a secure foot hold. Bi-planar heel: Sole design whereby the heel section is curved in two planes aligning with the natural curvature of the heel. This provides a more natural and earlier heel strike to aid descending and contouring. Webbing upper support is lacing attached to nylon webbing, which cradles and secures the upper behind the metatarsal heads. 11. 60 oz. Product measurements were taken using size Men's 9, Women's 10. 5. Please note that measurements may vary by size.