?Ultra-small Size?21 x 17.5mm, Seeed Xiao series classic form-factor for wearable devices. Part List: Seeed XIAO BLE Sense - nRF52840*1/7 Pins Header*2. ?Extra Onboard Sensors?One of them is a digital microphone created through Pulse Density Modulation(PDM) module on the nRF52840 chip. It can receive audio data in real-time which allows it can be used for audio recognition. The board not only receives audio data but also can speak through the MSM261D3526H1CPM microphone. The other one is 6-axis Inertial Measurement Unit(IMU) which can be applied in TinyML projects like gesture recognition. ?Rich interface?Firstly, the Near Field Communication(NFC) is functional on the board. Secondly, there is a tiny and elegant reset button on one side of the Type-C interface. It is designed in a three-in-one LED along with power LED. It supports UART, IIC, and SPI all three common serial ports. Same as Seeed XIAO RP2040, it has an onboard 2 MB flash which means it can also be programmed by Arduino, MicroPython, CircuitPython, or other program languages. ?Wireless Capabilities?XIAO BLE Sense has Bluetooth 5.0 NFC module with onboard antenna. With the capabilities of wireless connection, it still remains the Seeed XIAO series classic form-factor of small and exquisite which can be used for wearable devices and Internet of Things projects. ?Powerful CPU?As the advanced version of the board XIAO BLE, Seeed XIAO BLE Sense has equipped a powerful Nordic nRF52840 MCU which is designed in a Bluetooth 5.0 module, built around 32-bit ARM Cortex-M4 CPU with Floating-Point Unit(FPU) operating at 64Mhz.