Feature 1、USB Charging Port: Equipped with an external USB charging port, this backpack allows for easy charging by connecting power bank (not included) internally, connecting the phone externally, ensuring your devices stay powered up during outdoor activities 2、Humanized Design: Featuring a large main compartment and multiple combination pockets, this backpack offers categorized storage. The 180 degree opening main compartment makes it easy to pack and retrieve large items, enhancing user convenience 3、Efficient Storage Solution: With a thoughtful layout including dry and wet separation, this large capacity backpack accommodates items like wet towels and umbrellas, providing practical storage options and reducing travel burden 4、Vacuum Compression: After compressing items, the backpack offers extra space for storing small or loose items. The mesh zipper allows for secure closure. Additionally, it comes with luggage strap for easy attachment to suitcases, facilitating effortless travel 5、Water Proof and Sealed: Constructed with water proof polyester and 1680D nylon fabric, this travel backpack ensures no water penetration, protecting important documents and electronic devices from rain, making it suitable for all weather conditions 6、Product Details: Featuring metal zippers with tight teeth for smoother and easy pulling, adjustable shoulder strap buckles for personalized fit, and reinforced compression buckles to maintain shape even when carrying many items 7、Sturdy and Portable: Reinforced stitching on handle and shoulder strap stress points ensures long lasting durability. The soft handle design allows for comfortable carrying, making this backpack both robust and convenient Item Type: Travel Backpack Material: Water Proof Polyester, 1680D Nylon Fabric Product Color: Black Length: Approx. 32cm / 12.6in Height: Approx. 46cm / 18.1in Thickness: Approx. 16cm / 6.3in Expansion Thickness: Approx. 24cm / 9.4in Application: Store mobile phone, umbrella, headphone, wallet, computer, clothing, etc Capacity: 22L-39L-55L Power Interface: USB Pump Battery: Li Battery 1500MAH (built in) Weight: Approx. 1777g / 62.7oz Package List 1 x Backpack 1 x Pump 3 x Accessories 1 x USB Cable 1 x User Manual