Specification: Origin: Mainland China Style: A: 1 x Expansion board B: 1 x Expansion board + 1 x Development board Color: Black Green Material: PCB Option: Expansion board, expansion board+NodeMCU WIFI V3 CH340 development board (optional) PCB material: high-quality FR-4 material PCB layers: 2 layers PCB thickness: 1.6mm Size: About 70x60x15mm/2.75x2.36x0.59inch Weight: 30g Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement. Included: 1 x Expansion board Or 1 x Expansion board 1 x Development board 1. Efficient Pin Management: This splitter board expansion module allows users to conveniently manage pins, enabling easy reuse of pins for larger smart home projects. 2. Versatile Applications: With its reliable and safe design, this module can be used for a wide range of applications. 3. Double-Sided Design: The dual-layer design of the expansion board provides two pins on each side, increasing the number of possible connections and enhancing flexibility. 4. High Stability and Reliability: Using this splitter board, one GPIO pin on the NodeMCU V3 ESP8266 ESP-12E WIFI development board can easily be extended to two, providing an excellent tool for your project and breadboard replacement.