COMPATIBILITY: Designed for 38PIN narrow version ESP32 without mounting holes. Not compatible with other ESP32 versions. GPIO 1 TO 2: This breakout board expands one GPIO pin on the ESP32 development board to two, enabling full pin utilization in smart home projects. Ideal for breadboard-free setups. 2 TYPE CONNECTIONS: Features both pin header and screw terminal options. Choose based on your application needs. DOUBLE-LAYER PCB: Constructed with a double-layer printed circuit board. Wiring is implemented on both sides for enhanced stability and reliability, minimizing connection issues and signal instability. PRE-ASSEMBLED: This version comes fully soldered and ready to use. No additional soldering required. Dimensions: 77 x 63 x 10.5mm Material: Plastic Color: Green Package Includes: 1 x ESP32 Expansion Board Note: Other items not included. Note: Lighting conditions and display settings may cause slight color variations between the product image and actual item. Measurement tolerance: +/- 1-3cm.