100% brand new and high qualityDescriptions: Features: This product uses IOT chip ESP8266 for development board or T-OI WS2812 RGB for Expansion Board 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. The product is compact and the size design extends the size design of this battery holder. 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). We will design more convenient expansion modules to match the motherboard to facilitate the realization of various ideas for learners. Note: Light shooting 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 0-2cm. This product does not include 16340 batteries, picture is only for reference . Package Includes: 1 PC x T OI Development Board Rechargeable 16340 Battery Holder