"Dowsing Duplicates by Alexander Marsh is a great technique that can be used in a variety of ways. In the tutorial Alexander shows an actual stage performance with photo cards, then talks about using business cards, playing cards and questions cards to demonstrate the diversity of the principle. What I particularly liked was the ending he created which, after matching a couple of the cards individually, snaps into a quicker procedure to take care of all the other matches. It moves right along and doesn't get boring. As Alexander points out, these instructions can be adapted by performers in many different ways. Given my own style of working, I immediately decided that I would perform this routine wearing a blindfold such as my own stainless steel blindfold, a folded cloth blindfold or just about any other type. I, personally think the effect would be greatly enhanced doing it that way. But this is the good thing about this tutorial; it gives you the leeway to think about the effect and decide how you want to use it based on where you perform and who your audience is. Rest assured, the method can be learned in just 10 minutes and it is easy to do so you can devote your concentration on presentation. Highly recommended." -Richard Osterlind

"This is a very clever effect that gets a great reaction. There is nothing for the audience to discover because the entire secret is in your head! I really like this!" -Marc Paul

"Terrific, fooled me'" And so many wonderful variations , it will keep me up for days just thinking of them. 5 stars" -Marc Salem

Dowsing Duplicates by T.J. Osbourne is a psychometry routine with a difference. 

Using photos, borrowed business cards, playing cards, napkins, ESP cards or almost anything else you can think of; the mentalist is able to find the matching pairs amongst a sea of indifferent items.

The classic effect is as follows:

- 6 business cards are borrowed from members of the audience.
- They are stacked and torn in half, producing 12 identical halves. 
- The half-cards are mixed and laid out on the table face down.
- The mentalist impossibly finds each pair of cards, one after the other.

This is a truly impressive feat, as there is no way that the cards could be marked, or secretly peeked. 

Until you activate T.J.'s brilliant method in your mind, you really don't know where each card lies!

There are no difficult moves, nothing to be caught out on and the method works perfectly every single time.

After delving deeper into the method, We discovered that this can also be applied to a prediction effect, using a game like "Cards Against Humanity" or other similar "pairing" games. 

Even though each pair of cards is chosen at random, your prediction shows that you knew exactly what would be paired with what.

This method is something that you will carry with you for the rest of your days; as it lives only in your mind. 

After watching Alex's brilliant instruction, you will always have this secret ready to go at a moment's notice with no set up or special props required.