My dad gave me this lifting magazine that had these in it. They are crazy hand grippers for training your grip. One of them is so tough to do that only two men in the world can close it. Just curious if anyone here trains there grip to this extent? Oh yeah the trainer or beginner one takes 100 pounds of force to close while the normal one's you see at sporting stores are generally only 50 pounds. The number four that only two guys in the world can close takes 365 pounds of force!!