Fangrui Product Details : 1. Small In Size And Exquisite In Appearance, The Programmable Development Module Is Convenient And Beautiful To Wear. 2. The Development Board Is Used For The Development And Control Of Embedded System. 3. The Board Is Easy And Simple To Use And Operate. Just Connect The Usb Cable And Connect To The Computer, Open The Serial Port Driver Folder, And Install The Ch340 Driver. 4. High Quality Material Can Make Sure The Durability And Stability Of The Product. 5. Precise Production Process And Fine Craftsmanship Endow The Board With Good Contact Performance To Stable Work. Specification: Item Type: Programmable Development Module Working Voltage: Dc 3.7v Battery Type: Lithium Battery (built-in Battery) Battery Capacity: 500mah Purpose: For The Development And Control Of Embedded Systems How To Wire: 1. Connect The Usb Cable And Connect To The Computer, Open The Serial Port Driver Folder, And Install The Ch340 Driver. If You Have Installed It Before, You Dont Need To Install It. If You Cant Use It,