I have one that I use when my wrist hurts. If you cup it a lot, it can add some more revs but I don't put it at the most extreme settings. I try to set it so that it helps me mimic my normal free hand release, but it isn't the same. Also, if you're going to use it to help cup the ball, you might have to have your ball re-drilled since they can shorten your span a little.
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