COMPATIBILITY: Only suitable for 38PIN narrow version ESP32 without mounting holes. Not suitable for other versions. GPIO 1 TO 2: This breakout board expands one GPIO pin of the ESP32 development board to two, allowing users to reuse all pins in smart home projects. Ideal breadboard alternative. 2 TYPE CONNECTIONS: Pin header and screw terminal. Select based on your needs. DOUBLE-LAYER PCB: The expansion board features a double-layer design with wiring on both sides. Ensures stable circuit performance, reliable connections, and consistent signal transmission. UPDATED VERSION: Board is fully pre-soldered compared to previous version. No additional soldering required, making it easy to use. Material: Plastic Color: Green Package Contents: 2 x ESP32 Breakout Board Only the items listed are included; other products are not included. Note: Lighting and display differences may cause slight color variation between the image and actual item. Measurement may vary by +/- 1-3 cm.