【Durable Fabric】：Outer: High quality nylon composite waterproof fabric (Abrasion-resistant). Internal: Polyester 【Smart LED Backpack】: Unleash your creativity with LED Space App. We will continue to update the APP to bring you more GIF material libraries and a better experience! The backpacks can display texts, images, GIF animations, doodle 【How to Use】: LED screen is powered by external power bank (not included). Connect your power bank with the internal USB charging port. Connect the Bluetooth and use app for iOS and Android 【Design】: Adjustable shoulder straps with mesh fabric for superior back ventilation and support. You can buy it from Crelander 【Exterior Dimension & Space】: 17 X 11.8 X 5.1 inches. Capacity: 17L. The backpack can fit up to a 15.6" laptop
