Please Note: The backpack is not included pump Your needs to be purchased separately. pump is powered via USB 5V port. It can be easily activated using a mobile battery. Manual exhaust takes about 5 minutes. It takes about 1 minute to use the air pump Features: 2021 Design-Vacuum CompressiveThis backpack has a unique vacuum compression design. Is it a hassle to pack and store your backpack on your trip? When you put your garment in a vacuum cavity, you can pump it to deflate it, make it thinner, prevent a big sensation, and store more. Classic Black Business Backpack Made of durable and durable Oxford fabrics, classic black color, breathable sponge mesh design back and straps. One laptop compartment holds a 14.0-inch laptop for added security. [30-35L expandable design] The original capacity is 30 liters, dimensions 20.9 x 13.8 x 6.7 inches. After expansion, the backpack will be expanded to 35L. Closure with zipper and buckle according to your request. The upper and lower two handles are set and can be carried on both vertical and sideways, and it is easy to switch backpacks and suitcases. The rear luggage belt is designed to be fixed to the luggage tube. The outdoors & business backpack ideal for short trips for 3-6 days. [Large capacity & functions] Many compartments, organizing and expanded backpacks, you can easily organize storage items easily. Vacuum pockets mainly put clothing and pants. Front compartments can contain books, magazines, power banks, pens, data lines, and other travel supplies that need to be retrieved frequently. A universal inner bag can store private things such as passport, wallet, glasses case, and back compartments can especially put valuables such as laptops and tablets. [Durable and comfortable carrying] Our shoulders and handle are strong line sewing, load-bearing breathable and comfortable. Alleviate the pressure on the shoulder and make it tired even after transporting for a long time, and reduces pain. The zipper is smooth and strong, durable, and it is durable to use many times. Ideal for all outdoor activities, such as outdoor activities, new semester, university, commuting, business trip, hiking, sightseeing and camping. Unique products in the world(Vacuum compression backpack) 1. 30L space,It can hold 60Ls of clothes The capacity of normal backpack is 30L, which can reach 60 liters if use our vacuum compression backpack(depending on the clothes), it is close to the capacity of a 24 inch luggage (62L) Capacity of 20-inch luggage: 49*35*21=36L Capacity of 24-inch luggage: 58*41*26=62L Capacity of 28-inch luggage: 68*46*32=100L 2. Timesaving Most airlines request that suitcases over 20 inches must be checked, which means that after getting off the plane, you have to spend at least 30 minutes to get your luggage at the baggage claim area and then get out of the airport. Airports usually require passengers to arrive two hours in advance for check-in. If you use our vacuum compression backpack, you can pack as much clothes as those a 24-inch suitcase can contain. Therefore, there is no need for you to queue for luggage check-in. You only have to arrive one hour in advance to print your boarding pass and then board with your vacuum compression backpack. For one flight, we totally save you about one and a half hours. 3. Money-saving Many airlines offer budget tickets which are inexpensive but only entitle passengers to board with a 20-inch suitcase. Those larger than 24 inches must be checked, which results in an extra cost. Taking Spring Airlines as an example, a 15-kilometer luggage (almost equivalent to a 24-inch suitcase filled with clothes) costs USD 35. As for a round trip, it will take the passengers 450 yuan only for luggage check-in. As for the same seat, a regular ticket costs the passenger one or two hundred yuan more than a budget ticket does. As for a round trip, the price gaps would be USD 70. If you use our vacuum compression backpack, you can pack as much clothes as those a 24-inch suitcase can contain. Therefore, you can save USD 100 in total (USD 70 for luggage check-in and USD 30 for ticket fees). 4. Convenient When you go on a road trip, you only have to take a vacuum compression backpack packed with clothing that used to require a 24-inch suitcase. Our vacuum compression backpack only takes up a little space of your trunk. When you travel by high-speed railway with a our vacuum compression backpack, you can simply put it under or in front of your seat. However, if you take a 24-inch or 28-inch one, you have to put it in the aisle, which may cause you troubles. On one hand, you may forget to take your luggage when you get off. On the other hand, other passengers may take your luggage by mistake. When you travel by train with a our vacuum compression backpack, you can simply put it under or in front of your seat. You don't have to scramble fo