Item Type: LED Backpack Material: Oxford Cloth Power Supply Method: USB Interface APP: For SPOTLED APP Connection Method: Bluetooth Size: Approx. 41.91x31.75x14.99cm/16.5x12.5x5.9in Capacity: 21L Application: Can be used for advertising, holiday greetings, slogans, and commercial promotions. Perfect for commuting, travel, cycling, outdoor adventures, work, hiking backpacks, and even surprise gifts for friends. 1[Full Color LED Display] This backpack features a full color LED screen that can be programmed using a mobile APP via Bluetooth connection, making it easy to customize. 2[High Brightness] With a 64x64 high brightness dot matrix screen, this backpack supports text, image, and animation display, creating a cool and eye catching visual experience. 3[Large Capacity] Designed with ample space and multiple compartments, this backpack can hold various items such as bottle, books, wallet, pens, phone, power bank, tablet, and laptop. 4[Waterproof and Breathable] Made from Oxford fabric with a mesh back and high elastic cushion design, this backpack is waterproof, comfortable and breathable, features zipper closure, nestable with luggage handles. 5[Versatile Usage] Perfect for portable advertising, festivals, slogans, commercial promotions, and more, this backpack is suitable for commuting, travel, cycling, outdoor adventures, work, and casual use.1 x LED Backpack