Specifications: Scientific and reasonable design and construction, easy to carry, easy to use, inflatable balls can adjust the size of their own, neck rope can adjust the length, suitable for different height golf enthusiasts. This inflatable smart ball is connected to an adjustable rope to satisfy anyone's needs. It is currently on the market a very good training aids, can be used in the armpit, can also be inflated between the forearm. The smart ball will help you understand how the arms and body work during the effective golf swing. Using this golf intelligent inflatable ball practitioner can correctly grasp the swing posture, fix and strengthen the arms distance muscle memory, avoid arm bending, synchronize your body and arm, effectively improve the swing skills so as to m-aster the correct swing posture, find the right hitting point. It is a good training tool for golf enthusiasts to improve your swing performance through repeated training of intelligent ball practitioners for a short time. Item Name: Golf Swing Trainer Ball Material: PVC Ball Diameter: 15cm/5.91" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Golf Swing Trainer Ball(Black) 1 x Inflator(Random Color)