DIGITAL METRONOME IN-EAR SyncDancing is an ultra-miniature music player for ballroom dance practice that is placed in the ear, like an earphone. In addition to the metronome functions, 20 standard dance songs are built in, so you can practice anytime while listening to your favorite dance songs. This unit offers everything you need to improve your dance skills, sharpen your sense of rhythm, and familiarize yourself with various dance songs. You can practice alone, or synchronize the tempo using infrared, so that two people carry one unit each and can practice together.