This backpack can expands from 22 liters to 37 liters, with multiple internal and external pockets that help keep your belongings organized. It is a perfect choice fortraveling, commuting, business trip, and other outdoor activities. Features: Water-resistant oxford cloth material protects your belongings from the elements. Expands from 22L to 37L to hold your items safely and securely for convenient travel. Multiple compartments with plentiful interior pockets keep your items organized. Laptop pocket fits 15.6 laptop; special wet pocket for the wet sundries. External USB port offers a convenience to charge your mobile phone. Breathable mesh padded back panel and shoulder straps for extra comfort. Trolley strap allows you to attach the backpack to your rolling luggage. Great for traveling, commuting, business trip, and other outdoor activities. Specifications: Material: Oxford cloth Color: Black / Blue / Light grey / Dark grey (optional) Size: 32 * (17-29) * 48cm / 12.6 * (6.7-11.4) * 18.9in Weight: Approx. 1.1kg / 2.4lb Package List: 1 * Backpack