The Nomatic Backpack 20L was designed for everyday use. Its made with durable, water-resistant materials and YKK zippers. Starting at 20L and expanding to 24L, this bag is slim but expands when you need to pack more. The patent-pending strap system allows you to go from backpack to briefcase carry for those times when you need to look more professional. The full perimeter zipper, magnetic water bottle pockets, RFID safe storage, and hidden pockets, are just a few of the 20 noteworthy features that make this backpack the most functional backpack ever!