This is a very rare Supreme Magic product that was made over 40 years ago. It is deviously clever and the mechanism works flawlessly.
The apparatus consists of 3 plastic glasses. Two of these are shown to be empty, the other contains milk or (OOM). The audience also see two paper tubes that are easily made from a business envelope. An empty glass is placed on the table. Over this, completely covering it, is placed one of the paper tubes.
Now a small square of plastic is shown. (Two are supplied: one is clear, the other colored. You can use either one of them.) On top of this plastic is placed a second glass. This is covered with another paper tube.
Performer now lifts up the third glass which contains milk or any liquid. He pours the mik into the top glass. He then lifts the paper tube. The audience sees that the milk is definitely inside the glass. The tube is replaced. He continus pouring all the milk into the glass at the top
Now he commands a penetration to take place. He lifts off the top paper tube. To the surprise of the audience, they see that the top glass is now empty. The milk has vanished! (If the audience has any theories about the milk being inside the paper tube, the tube is squashed flat and can be tossed out to the audience.)
The glass at the top is lifted away, the plastic sheet is removed and shown. Finally, the paper tube at the bottom is lifted up to show that the milk really has penetrated right through.