Overboard Waterproof Pro-Sport Backpack 100% Waterproof - Roll-top fully waterproof backpack, floating safely if dropped in water. 2-way sealing system and welded construction - With traditional top or side compression protecting contents from dust, sand, dirt and water. Front zip mesh pocket - For secure storage of smaller items. Padded shoulder straps and lumbar support - For a comfortable fit and feel when carrying even if fully packed. Ventilated back panel with air-flow design - For enhanced ventilation to keep you comfortable and dry.