For extra support and waterproof, breathable comfort, the Merrell Siren Song Mid GTX meets the trail head on. Merrell Siren Sport Video. QForm triple density EVA midsole for cushioning, support, stride alignment. Molded nylon arch shank reinforces the arch for added support. Vibram TC5 rubber outsole for excellent grip on dry and wet ground. Gore Tex XCR membrane keeps feet dry with excellent breathability. Synthetic leather and breathable mesh upper for durability and support. Air Cushion in the heel centers and stabilizes the foot and provides shock absorption. OrthoLite anatomical footbeds inhibit odor, add cushion, and wick moisture. Stroebel construction offers flexibility and comfort. Hook and loop lacing closure system for quick adjustability. Protective leather rand and abrasion resistant heel bumper. 6 mm sole lug depth for solid grip.