Vacuum Compression:The air backpack adopt in vacuum packet design,not only save space but also let your travel be convenient, It also provides you with an electronic vacuum pump for you to choose. This air pump can be used for both suction and blowing, and provides various nozzles that can be used in a variety of scenarios. The air pump also has lights, which can provide you with lighting when traveling at night. Expandable Capacity:Vacuum backpack before extended is 20L, dimensions are 20.4x11.8x7.8inch; after extended is 36L, dimensions are 20.4x11.8x11inch. You can expand the zipper and buckles according to your requirement. The two handles set on top and one side, which allow an easy switch between backpack and suitcase. So it can be carried vertically or horizontally. About Detail:Air backpack wither Vacuum withe vacuum seal all zipper made in durable BBS zipper but the vacuum pocket uses high-density vacuum specific zippers, making it difficult to open, but this is to ensure the top secret protection performance of the vacuum pocket.Meanwhile,the laptop backpack have lot of human design,such as adjustable chest strap,breathable shoulder strap,luggage strap, TSA lock and anti-theft pocket. Multifunctional Pocket:The travel backpack have four main pocket,the front pocket can lay pen,ipad,magazine,umbrella and so on.the main pocket have shoes compartment and wet and dry separate pocket and the important vacuum pocket not only can save your space,but also can orderly store away your every goods,the laptop compartment can hold 15.6 inch laptop and 9.7 inch iPad and we increase in height design of the part, so your don’t worry about your laptop. Waterproof material:The bange vacuum backpack made of high-density coated oxford fabric not only waterproof and resistant but also scratch-resistant.you don’t worry rain day of your backpack.but the zipper don’t waterproof,so can not be exposed to rain for a long time.This item is not intended for use by childer 12 and under. The commute backpack made of high-density coated oxford fabric not only waterproof and resistant but also scratch-resistant, you don’t worry rain day of your backpack.but the zipper don’t waterproof,so can not be exposed to rain for a long time.The backpack L:11.8nch*H:18.5inch*W:6.2inch,can hold 15.6 inch laptop,suitable as overnight,commute ,business travel and daily backpack,and the laptop backpack belong approved fight approved,you don’t worry about the carry on size.The laptop backpack have four main pocket,the side pocket can hold kettle or umbrella,the laptop compartment can 180°open suitable for 15.6 inch laptop and 9.8 inch Ipad,the main pocket have wet and dry separate pocket so you don’t worry your electronic device and the item large capital can store 4-5 pcs clothing,the overnight backpack back have a anti-theft pocket can fit in your wallet or other valuable goods.Multi-function shoulder straps with card pocket you can easily take your credit card, and have glasses hang bucks,the key chain convenient you find your key, the backpack made in YKK zipper not only smooth but also durable,The 3.0USB charge port and luggage strap be convenient for your holiday or daily needs outdoor