Prediction with a marked gum blister pack
A marked compartment matches the choice
In this prediction, the spectator sees a pack of gum and understands that one of its compartments has been marked with an X. They then name a row and a position; upon sliding out the blister pack, that is the compartment shown to be marked.
Julio Montoro explains the crafting of the gimmick and the handling of the sequence. The choice of position is free within the layout of the presented package. The marking is done on the prepared plastic using a permanent marker: the class teaches how to associate it with the announced position.
The package and the small shell
You need the pack of gum with its sleeve, another blister pack of the same type to craft the auxiliary piece, scissors, and a permanent marker. The setup is explained using packages that Montoro identifies as Trident and Oral-B, featuring compatible pocket shapes.
In the example, there are ten positions distributed across three rows of three, four, and three. The important thing when preparing another package is to check the shape and fit of the cells, as well as adapting how the choice is explained. The lesson does not rely on buying a magic product.
Montoro demonstrates how to empty a pocket of the extra package, clean up its residue, and carefully trim it to obtain the shell. A visible mark is then prepared, which can be an X or another drawing. The fit of the piece and the pressure with which it seats over the chosen position are worked out.
Presentation and handling of the choice
The explanation covers bringing out the package, introducing the marker, and the moment of putting the package away. It also teaches how to use the action of putting away the marker to retrieve the prepared piece and keep it concealed until needed.
Montoro reviews how to describe the rows and positions so the choice is clearly understood. He then shows the extraction of the blister pack and the move used to place the shell, covering the action before revealing the mark.
Examples are explained for different rows and a specific position that can take advantage of an opening in the sleeve. The learning lies in coordinating the announcement of the choice, the removal of the package, the hand coverage, and the final display.
Showing the mark and handing out a piece of gum
Once the piece is set, the tutorial shows how to offer a peek and allow the spectator to touch the indicated compartment. Montoro discusses the pressure and fit necessary for that display. He also teaches how to take out a piece of gum and hand it to the spectator as a kicker ending.
The mark is made with a permanent marker on the blister piece; the handling of the package remains a part of the effect. It is advisable to practice the placement and the method of displaying it using the exact same package you will use in performance.
Variants and scope of the lesson
A variant is developed using the empty blister pack to change the way the X is shown. That version requires its own cover when placing the piece, because the transparent compartments reveal more than in the full pack of gum.
An idea of visually sliding the mark is also mentioned, but Montoro focuses the resource on the prediction and shares his reservations about that additional application. It is not presented as a second full routine of equal weight.
This is a lesson for anyone who wants to craft a small mentalism piece using an everyday object and carry it with them. The manufacturing uses very few materials; the practical work is in the fit of the shell, its concealment, and the tie-in with the free choice of row and position.