I use the Magic Carpet, it is about the size of 4-5 pieces of white tape. It gets a snug fit for the thumb and a clean release. I probably didn't need to open the thumb up very much, I find I am still putting in 5 or more pieces of tape.
The idea behind the carpet is it allows a tight fit without the vacuum forming that prevents a clean release. It takes some getting used to how snug you can get the thumb. I tried the Magic Carpet in North Carolina and Ron kept telling me to put in more tape. I wasn't sure the ball would come off the hand, but he knew what he was talking about

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USBC Bronze Coach "I cannot change the direction of the wind but I can adjust my sails to reach my destination." Jimmy Dean
Quaker 10/93 - 4/07

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