The photo below shows the three basic components for the ROV camera:

Top/left is the video balun which the case and coax "pigtail" removed. Top/right is the composite video camera, and bottom is the marine grade tubing.

The components are connected as follows:

The final assembled version looks like this:

Note that the video balun is passive (un-powered); power from the surface only goes to the red wire of the camera.