Golf Swing Trainer GST-3G Atlas Golf Swing Trainer Head Swing Measurement Device This device measures head swing, ball speed, distance, and sweet spot ratio for swings, as well as ball speed and distance for putting. Requires 4 AAA alkaline batteries. Box and batteries are not included. There is a feeling of use due to it being a used item. The cover seal from the time of purchase is still attached. Please check the photos before purchasing. Please refrain from price negotiations. Immediate purchase is possible. Type: Distance Measuring Device