Features: The Expansion Board is a powerful :Bit accessory that connection to 19PINs of the :Bit board, enhances functionality for your projects. Each PIN comes with corresponding VCC and GND, allowing flexible switching between 3.3V or 5V, and features three independent 3.3V and 5V pin for versatiled wiring option. For students, educators, maker and programming enthusiasts enhancing their hands on skills and coding abilities. Perfectly for classroom teaching, maker space, and lab, this expansion board facilitates innovative projects like home systems. With compatibility for I2C communication and onboards passive buzzering, the bit Expansion Board opens up possibilities for connecting LCD displays and more, making it essential tool in your electronics toolkit. Specifications: Item：:Bit Expansion Board Compatibility for I2C Communication Switching between 3.3V or 5V Size:about 57x39x15mm/2.24x1.54x0.59in Power Supply: DC2-12V Package Includes: 1PC :Bit Expansion Board note: 1cm=10mm=0.39inch Due to problem of lighting effect, there nmightbe certain tolerances in product, please understand. Please allow 0-1cm error due to manual measurment.