The Bebob Engineering BE-AML-120ALEX is a Hot Swap Adapter for the Alexa Camera which allows you to swap the battery without interruption of the camera powering. When the battery runs empty, the ML-120A will take over the powering of the camera for 2 minutes, giving a simultaneous alarm. The ML-120A replaces the Standard V-mount on the Alexa, or other 3rd party battery mounts. Additionally, it features a 12 V DC D-Tap port, secured by a 5 A self-resetting fuse. After use, the ML-120A self-charges from the camera battery.