Wrist snap is automatically developed and stored as muscle memory. The end mounted weight combined with the flexible rope handle automatically snaps the wrist through the pitching motion, resulting in increased speed. Corrects bad habits. Forces the player into the correct pitching & throwing plane that leads to increased speed. Great for general arm warm up prior to practice or game. Beneficial for conditioning of the arm and shoulder. Training can be done without the use of a catcher and can be used indoors for year around practice. With softball size ball.