I bought these years ago when they were sold through a different company, Dragon Door, and under a different name, Neuro Grips. Its leading champion was the strongman, Jon Bruney, who was built like a unit. I was doing a lot of calisthenics at the time and since regular push ups were too easy, I gave these a try. The first time using them was a humbling experience! It revealed to me how weak my wrists and hands were. I think I might have gotten one shaky rep. They definitely make the traditional push ups harder, and they make your hands, wrists, and forearms stronger in the specific movement pattern of the push up. Nonetheless, I think these are of somewhat limited value (at least for my purposes), because I didn't experience noticeable carryover to traditional barbell movements like the bench press. But if you train calisthenics often, and want a way to make push ups harder, they might be worth it to you. One important tip on using them: avoid hard surfaces that are relatively smooth (e.g. concrete or marble floors), on pain of faceplanting. The good 'ole horse stall mats work best for these, as they help to avoid slippage and allow the equipment to challenge you.
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Build Quality