link for those who dont know- https://www.vharness.com/
The V Harness
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Hey I have been using it for a few years now and it really helped, I have tried a glove under the arm but I really like this it makes it easier to relax my arms and concentrate on using my core. It's really something that you have to feel in order know what it's like. They have a couple of cool vid's about jimmy ballard and their swing trainer.