Build a Jockey Box in under 7 Minutes! 

I am a bit confused by this video. You mention that the red line is a gas line and the clear is your beer line. How does beer get into the plate? I see gas going into the plate and somehow, magically, beer comes out. Should we assume that the red line is actually a beer line coming in from a keg? I noticed that the ball lock coupler is also the gray gas line version instead of the black beer line side. Please help me understand where this amazing device pulls beer in. Thanks.

Better off filling it with ice and beer unless your drinking by your self lol