Feature:1. EDIT IN THE APP : The content on the LED screen of this hat can be freely edited using the mobile app , which is perfect for outdoor concerts, baseball, carnival, Christmas, bars , clubs, holiday parties, Halloween and more. 2. REMOVABLE SCREEN : If you don't want text to appear on your hat, you can turn off the power and use it like a regular hat. The LED screen can be disassembled and used elsewhere. 3. SIZE ADJUSTMENT: There is a reasonable adjustment buckle on the back of the hat. Can be adjusted to the size of the head. You don't have to worry about the hat being too big. 4. COTTON MATERIAL: This smart LED cap is made of cotton fabric and is comfortable to wear. The top is thickened, which does not easily deform or collapse and does not affect the appearance of the hat. 5. EASY TO USE: Download the app to your phone, press and hold the power button to activate the LED screen , then connect to the Bluetooth hotspot on your phone, you can start editing. . LED Cap Programmable Application Control Specification: Item Type: LED Cap Material: cotton Battery: 1 x 602040 Lithium Polymer 450 mAh Battery ( Built - in ) APPLICATION: For SPOTLED applications Connection Method : Bluetooth . LED Cap Programmable Application Control How to use: Remove the product and use it . . LED Cap Programmable Application Control Package List:1 x LED Cap 1 x USB cable . LED Cap Programmable Application Control