Key benefits Expands Micro:bit IO with 19 pins, giving you more flexibility for projects and experiments. Perpin power option: each IO pin has a corresponding Vcc and GND, and you can switch the supply to 3.3V or 5V using jumper caps. Convenient power rails: dedicated 3.3V and 5V pins are provided for easy power distribution and wiring. Builtin buzzer: an onboard passive buzzer is available and can be used via a jumper cap for audible feedback or alerts. Enhanced I2C compatibility: SDA and SCL pins, plus 5V and GND rails, support module connections such as LCD1602 displays for expanded communication options. What it is and compatibility A micro:bit compatible IO bit expansion board that extends the micro:bit's pin count to 19, enabling more complex and featurerich projects. Power and pin details Each pin on the board has an associated Vcc and GND line. Vcc for each pin can be set to 3.3V or 5V via jumper caps, offering flexible wiring for different sensors and modules. The board includes dedicated 3.3V and 5V pins to simplify power distribution in your projects. Key features 19 IO pins to interface with sensors, actuators, and modules. Onboard passive buzzer connected via jumper cap for simple sound output. SDA and SCL lines plus 5V and GND pins for easy connection to I2C peripherals such as LCD displays (e.g., LCD1602) and other I2C devices. Use scenarios Prototyping sensor arrays: connect multiple sensors to the 19 IO pins, using perpin 3.3V/5V selection to optimize power for each device. LCD or I2C module projects: utilize SDA/SCL with 5V/GND rails to drive LCD displays or other I2C modules, enabling richer user interfaces. Audioenabled micro:bit projects: leverage the builtin buzzer to provide audible feedback or alerts without needing additional hardware. Notes The description preserves the original board's function, compatibility with Micro:bit, and the demonstrated features (perpin Vcc switching, buzzer, and SDA/SCL support) without adding or omitting details.