Feature: 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. 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 don't need to install it. If you can't use it, the driver version may be too low and you need to reinstall it 2. When developing a programming program for the ESP8266 watch, the upper and lower boards need to be connected to the cable and turn on the switch to burn normally. (Due to different product batches, the appearance may be different, which does not affect use.) Color: Black Material: Plastic+metal Package Contents: 1 x Programmable Development Module 1 x Strap Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.