Merrell Chameleon Prime Stretch hiking shoes offer an athletic fit that feels snug and secure. The adaptive and aggressive traction design will grip to whatever conditions you may face during the day. You can easily tighten them to the perfect fit with the secure, one-pull tightening system.Upper: Leather and synthetic materials provide durability and support. Mesh offers breathable flexibility. Bellows tongue will help keep out debris.Midsole: Breathable mesh lining with M Select FRESH naturally prevents odor before it starts. Removable EVA footbed treated with M Select FRESH. Molded EVA footbed. Molded nylon arch shank. Outsole: M Select GRIP tunes each outsole with durable traction that grips when and where needed. 4mm sole lug depth. Merrell air cushion in the heel absorbs shock and adds stability.