The Salt Pen by Bill Montana

The Salt Pen is a simple gimmick that allows the user to secretly mark a group of items for identification later in a mentalist routine after a spectator has made a free choice of one of the objects.  Don't underestimate the power of this "radar" type pen.  The uses are endless, and it doesn't take a lot of creativity to conjure up many different applications, that could be incorporated in the same setting, using just this one special utility prop.

An exceptionally detailed, and through 18 page manual that takes you step by step, regards to how to construct one of the most simple and effective tools in magic. Used by magicians (Dai Vernon), and mentalist a like.  It's brilliant in its simplicity and effectiveness because it's one of those unique tools that is right in front of their very eyes, yet also invisible too.

This work really features exceptional illustrations, photos and script.  Everything you will need to know is not only within but laid out in an easily digestible manner.