Full Grain Leather. Metal Hooks and D-Rings for Secure Lacing. Bellows Tongue Keeps Debris Out. M Select™ FRESH Antimicrobial Agents Reduces Shoe Odor. Breathable Mesh Lining. Merrell Air Cushion in The Heel Absorbs Shock and Adds Stability. Merrell Kinetic Fit™ BASE Removable Contoured Insole for Flexible Support. Compression Molded EVA Midsole for Stability and Comfort. Vibram® Megagrip®. 3 mm Lug Depth.