I'm considering getting one. Just wanted to know if they actually work and if anyone has used one. 
always been curious myself, what do those thinga do?
It spins fast. causes co-contracting of all the grip muscles. commonly uses in occupational therapy. Played with one at a rock climbing gym, shit almost flew outa my hand. fun to use but haven't spent enough time using one to know if its worth it. 
I used to have one, they're pretty cool but I never used it enough to get any real benefit out of it. They definitly work if you're motivated enough to use one.
I met a guy who said his carple tunnel was so bad he couldn't make a fist. He said after using one of those things his wrists were back to normal. I don't know, I used one a lot when I was drumming more. Haven't touched it in years.
I bought 10 from Woolworths just before they closed down for 99p each. The resistance isn't really scalable/progressive so it's more of a boredom exercise than an actual training tool.
Kinda like...
I tried it. It's a novelty.
FJJ828 -
Kinda like...
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