US Patent 7686711 Batting swing aid

A batting swing aid fitting onto the barrel of the bat to assist with hand speed when swinging a bat and having an outer body and an inner body. The inner body has four chamber compartments each of which is filled with an equal amount of shot. As the bat is moved to the proper hitting position the shot travels down the inside chambers to make a swoosh sound at the impact zone. During the proper swing pattern the swoosh sound will be closer and closer to the proper impact zone. The device helps build power, and repeating the swing with the additional weight increases the power of the batter and help create proper batting muscle memory.