Train your grip, wrist and forearms at the same time—becoming strong in all directions. Train both concentrically (winding up the cord) and eccentrically (allowing it to unwind under control. The IronMind Twist Yo' Wrist could be the missing link in your lower arm training—the key to better performances whether you are a martial artist, arm wrestler, hand gun shooter or rock climber. Fun to use and very effective!