Yeah, I have the red one and the green one. I never did much with them, as they didn't seem to help. What helped most was lowering my tension, getting an elbow band, and taking it easy. I also worked with a pro on my FH form so I use more body and less arm. Even now if I start arming the ball too much, I will feel the elbow.
I heard you really should start with the red one and work up to the green one, FWIW.
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