MATEIN Vacuum Backpack Travel with Hand Pump, Waterproof Carry on Backpack with Vacuum Compression for Airplanes, TSA Personal Item Travel Bag Fits 17 inch Laptop, Airline Approved Suitcase, Black Made of high-quality waterproof fabric and featuring waterproof zippers, the vacuum backpack travel with pump offers 5 compartments and over 12 pockets. All for smart organization and space-saving efficiency, travel lighter and smarter! Please Note: Only hand pump included What type of electric air pump can be used on this backpack? Generally the electric air pumps available in the market come with nozzles in various sizes. The air valve hole on our vacuum backpack has a medium-sized diameter of 0.7 inches (1.8 cm). So don't worry about the compatibility between pump and bag! How to use vacuum compression with hand pump? First, open the air exhaust valve. Second, pack the clothes and zip the vacuum seal compartment to the top to keep it sealed. Third, use hand pump to pump up & down against the valve port to pump out the gas in the bag. And then close the gas valve. Why are zippers on vacuum section so hard to close? Need to zip it to the top? 1.That's because our zippers are designed to be airtight, ensuring a tight and secure seal. 2.Definitely yes, you need to zip the vacuum compression compartment to the top to keep it sealed. Does this vacuum travel backpack fit in the overhead bin or under the seat? Indeed, it does. The vacuum backpack sizes at 18”(H) x 14”(L) x 8”(W). It meets most airlines' personal item size limits, helping you avoid extra baggage fees on your flights! Is this personal item backpack comfortable and sturdy? Yes. Our vacuum backpack is crafted from premium waterproof fabric with waterproof zippers, stands upright and maintains its shape. Featuring djustable straps, breathable mesh back, and chest strap, ensures all-day comfort and reduce shoulder strain. To create products that inspire people to get out and live passionate lives; exploring, creating, and living life in the moment!