You can use the Cisco Wireless IP Phone 8821 and 8821-EX Desktop Charger to charge your phone and spare phone battery. The charger works on AC power or from a charged spare phone battery. It can be secured with a standard laptop cable lock. If your phone has a protective case, you don't need to remove the case before you charge the phone in the desktop charger. You adapt the charger to fit the phone. You can use a USB to Ethernet adapter (dongle) to connect the desktop charger to the Ethernet for only automatic Wi-Fi profile provisioning and certificate enrollment purposes. You cannot use the dongle to make voice calls over the Ethernet.