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Are you thinking about the Permanent Brain Enhancement audio? It does give permanent results. It requires daily listening for permanent results.
The more you listen to it, the more permanent the results are.
Please read this post for more information.
The results you get from Core Strengthening are the same as the results you would get from working out your core muscles. The results are permanent to a degree, results will stay with you for a while but the muscles will atrophy if not used for a long time.