These do work if used regularly. I got them mostly for climbing and my hands and forearms are taking a lot longer to tire on the wall after a couple months use. Blue was actually quite hard at first, I was struggling to open them all the way even one time but in a month or so i was able to do sets of 15, no prob. Im happy with the results so far.
I bought for myself and a friend. Both of us lift and these have been a nice addition to ad in at the end of our workout for burning out the forearms and have worked surprisingly well. They defiinitely hit the extensors and stabilizer muscles on the back of forearms that is unique. I was not expecting them to give me the pump that they do! Way more than I expected. Thanks and would recommend.