Please read the self-introduction profile. This is a swing training device that can be used by beginners to advanced players. By swinging with both arms through this trainer, you can feel and improve the synchronization of your arms and body, and all bad habits of hitting with your hands. 13 years ago, I was instructed to use this by someone who coached a female professional golfer who was competing for the prize money queen during her junior days. At first, I reluctantly agreed because I thought it was uncool to practice with such a thing at my age. However, by incorporating it into my practice routine every time, I began to intuitively understand the synchronization of my body, eliminated the habit of my elbows flailing when I got tired, and consistently started shooting in the 70s. I also won several tournaments. I no longer play golf, so I would be happy if someone could use it. Thank you very much. #SwingPractice #SwingTrainer #SwingMaster