Features
1. Added 16340 electrical socket to the ordinary development board, which can use the corresponding rechargeable 16340 battery to power the system, which is convenient, beautiful and practical.
2. The product is compact and the size design extends the size design of this battery holder.
3. All IO ports are reserved from both sides, compatible with the distance between MINI D1 extended version and breadboard. Grove interface is reserved at the same time, compatible with Grove interface module, and T-Watch sensor module (T-Watch special connection cable needs to be connected).
4. We will design more convenient expansion modules to match the motherboard to facilitate the realization of various ideas for learners.

Hardware Specifications
1. Chipset: ESP8266EX
2. USB to TTL: CH340K
3. Charging chip: TP4054
4. FLASH: 4MB
5. Size: 43.96x25.63x20.80mm
6. Weight:7.87g

Power Supply
1. Battery: 16340 3.7V rechargeable lithium battery(not included)
2. Battery switch:Yes
3. USB: Micro USB

Wi-Fi
1. External antenna mount: With IPEX antenna mount
2. WIFI antenna: Ceramic antenna