BL654 Noridc SDK/Zephyr USB Adapter Ezurio BL654 Nordic SDK/Zephyr USB Adapter is a BLUETOOTH® v5 USB Adapter that offers complete flexibility to utilize the hardware with Nordic/Zephyr environments. This BLUETOOTH USB adapter features a secure pre-programmed bootloader and offers development flexibility. Typical applications include IoT devices and sensors, beacons and proximity applications, secure medical peripherals, and BLE mesh.