The performer displays two tubes with caps. Two different colored tissue paper balls are dropped- one each into the two tubes, and capped. When the caps are removed, the paper balls are found to have changed places.
Everything can be examined.
This is just one effect you can do with these props. You can transpose or change many small items that will fit in the tubes (beads, liquid, sugar or salt, Smarties or other small candy, paper balls, beans and peas etc.
Complete with the pair of precision made tubes in plastic and instructions for several applications.