Quick Prototyping:Easy debug and Reset with RESET button and SWD pin led out to the male header. 0.96inch OLED, enables visual data to display without PC serial monitor. Rich peripherals:OLED display, RTC, expandable memory space, passive buzzer, user button, on board battery management chip etc. One board on hand to explore the infinite possibilities of Seeed Studio XIAO series. Mini Size:Compact and elegant with only half for Raspberry Pi 4 size, perfect for tiny and wearable projects. No Soldering Needed:All pins are led out. Convenient plug-and-play Grove connectors support multiple data protocols, including IIC, Uart, and Analog/Digital. Circuit Python Supported:Well supports circuit python. Mini SD card slot enables memory space expansion, making it possible to allocate more libraries needed in prototyping and project building. Colour:As Shown Material:PC Package Contents: 1 x Expansion Board Base(Due to different product batches, the appearance may vary, which does not affect the use)