Features: 1. IO: bit expansion board is a for :bit expansion board, which leads to 19 PIN pins of the Microbit Board. 2. Each PIN pin has VCC and GND corresponding to it. You can freely switch VCC to 3.3V or jumper cap. 5V; with 3 3V3 and 5V pins, the wiring is more flexible and diverse; 3. I2C SDA and SCL pins and the corresponding 5V and GND pins are provided for module connections such as LCD1602 LCD display for I2C communication more possibilities; 4. With on-board passive buzzer, connected via jumper cap; 5. Power supply includes DC head and USB socket power supply. Parameter: Power supply mode: USB power supply, DC head power supply (6-12V) Power function: power indicator Voltage stabilizing circuit function: can carry 3.3V/5V load Audio function: a passive buzzer Separate 4Pin I2C 5V pin 19 PIN IO outgoing (all IO and P0- of -biological are outgoing) Material: PCB colour: Black Package Contents: 1 x for microbit expansion board Only the above package content, other are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.