E104-BT5040U uses nRF52840 chip, and the factory firmware supports CONNET, plug and play. It has rich peripheral resources such as UART, I2C, SPI, ADC, etc., which is convenient for users to carry out secondary development. Uses 32M+32.768kHz industrial-grade crystal oscillator. Supports Bluetooth 4.2 and Bluetooth 5.0. The module functions and pins correspond to the official nRF52840 USB Dongle module of Nordic, and are compatible with all programs of the nRF52840-Dongle. Product model: E104-BT5040U. Operating voltage: 4.3~5.5V. Operating frequency band: 2360~2500MHz. Chip solution: nRF52840. Transmitting current: 17.05mA. Receiving current: 8.27mA. Transmitting power: 7.5~8.5dBm. Reference distance: 250m. Supported protocol: BLE4.2/5.0. Interface mode: USB/1.27mm hole. Interface: PCB onboard antenna. Color: Blue. Material: plastic. Package Contents: 1 x E104-BT5040U Bluetooth Module. Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.