Merrell Siren Sport Gore-TEX Women's Walking Shoes - SS17 Strobel Construction - Offers flexibility and ultimate comfort. Synthetic Leather/Mesh Upper - Yields excellent flexibility and breathability. Bellows Tongue Cover - Prevents mud and debris from getting inside the shoe. Ortholite Anatomical Footbed - Combines a specific Ortholite foam and air cushioning to help improve comfort and fit. GORE-TEX Extended Comfort Footwear Lining - Keeps your feet dry from the outside as well as from the inside.