Flexible Strobel Construction. Waterproof Leather or Synthetic Upper. Marine Guard Toe and Heel Reinforced Protection. Breathable Mesh Lining. Removable Anatomical EVA Footbed. Nylon Arch Shank. Sebago Blue Wave Vibration Dampening Technology. Cushioned EVA Midsole. Sebago Energy Return Pad. Sebago TriWater Deck Sole with Slip-resistant. Non-marking Rubber.