Description: Golf Swing Trainer: impact, Practice Aid with Adjustable Neck Lanyard, Lightweight, Durable and Portable. Uses: It can be used to correctly grasp the swing posture, fix and strengthen the arm distance muscle memory, and avoid arm bending. High Quality Material: Made of PVC, it can be used flat or under the arm or between the forearms. FIT: Helps you understand how your arms and body work during an effective swing, get the correct swing, and find the correct position to hit the ball. Practice Accessories: Ideal for beginners to practice and professional to teach and improve swing performance. Specification: Material: PVC Size: Approx. 15x15x15cm/5.91x5.91x5.91inch Package Includes: 1 Golf Swing Trainer ball 1 Inflator Note: Please allow slightly errors due to manual measurement and different monitors.