Commuter designed backpack comes with waterproof replaceable liner and a classic heavy-duty 20oz cotton canvas exterior. The large, open interior is 100% waterproof. It will most likely fit more than you should carry -- but it was designed for bike commuters, so your change of clothes, lunch, shoes and laptop will fit just fine. Pockets under the flap; one large zippered pocket, a medium sized flapped pouch and pencil pockets complete the bag. Comfortable fit for riders from 158cm and up.