How do I do this magic trick involving a ring?!

Question: I saw some videos on youtube. This is one of them. I have lots of different rings so what would be the best o you think? And how do I do this trick? I wanna know!
http://www.youtube.com/watch?v=Cg-JND9h3...

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Answers: I saw some videos on youtube. This is one of them. I have lots of different rings so what would be the best o you think? And how do I do this trick? I wanna know!
http://www.youtube.com/watch?v=Cg-JND9h3...

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http://www.ellusionist.com/product/dvd+t...

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