The Boss Dr. Beat DB-30 Metronome makes it easy to accurately keep time during practice. Built small for slip-in-your-case portability, a headphone jack lets you practice anywhere silently. It's easy to use, too, with a large LCD and controls for power, volume, start/stop, tap/mute, rhythm/beat, note/pitch, and tempo/value, plus lights and on-screen needle for visual feedback. More than just an adjustable click, Dr. Beat can lay down 9 different patterns, 24 beat variations, rhythm styles, and combinations to play with.