This custom military rucksack is made of heavy duty nylon fabric. It's waterproof and durable, also big enough to hold your laptop, tablet, phone, wallet, umbrella, water bottle and other essentials. Built in a USB charger port, You can place a power bank, an external USB charging port to ensure that your phone’s battery is always and everywhere saturated. The large compartment is suitable for books or laptops, and the mobile phone bag and the ID bag are also provided; the buckles are cleverly designed on both sides of the backpack to better stabilize the backpack. This simple and retro assault pack is perfect for outdoor activities such as cycling, camping, hiking, travel and more. Suitable for all adult men, women.