Used Yupiteru GST-5 W distance measuring device. Includes the main unit, instruction manual, and charging cord. It was working without any problems until recently. The panel has some fine scratches. Using this made monotonous practice fun! It's also helpful for understanding the distance of each club. You can check your head speed, ball speed, distance, and smash factor. To use it, just place it behind the ball. You can easily see your history and average values. It also has a distance correction function. It's a convenient rechargeable type. When fully charged, it could be used for about two weeks with about an hour of practice. Thank you.