The VLM-FX9 is a direct V-Lok fitting for Sony's FX9 camera allowing the user to use higher powered V-Lok batteries rather than BPU batteries which are the standard battery for the FX9 camera. The adaptor attaches via the lock in mechanism in the FX9's battery compartment and then finally screwed to the top of the camera body to secure in place. Users have the benefit of 2x Power-con (D-Tap) outputs 11 - 17 volts allowing further equipment/accessories to be powered. 1x 5V 2A USB is also available for powering or charging accessories such as mobile phones. Power is provided via a short DC jack cable via the FX9's DC Input. A low voltage warning LED is also situated at the top of the fitting, this is to combat the camera as it will only ever see the 19.5v in the viewfinder. So no warning would be given when the battery is low. The LED will flash at 11.5v, giving you a decent warning to make a change.