First time I saw something like this was 40+years ago in a car wreckers yard. They used it to drain the fuel tanks on the cars that came in. It consisted of a piece of 3/4" Clear PVC tube and a short length of copper pipe with one end rounded over a little with a glass marble inside and a small dimple about an inch back up the copper tube from the marble so it didn't come out and that was fitted to one end of the PVC tubed. It was placed into the bottom of the fuel tank (just like the video) and jiggled up and down to prime it and once the fuel came up over the top the natural syphon took over. Worked a treat.