This is Wittner most popular compact pendulum metronome. This is the original, compact, pocket-sized metronome (5-1/2″ High) in a durable plastic case. This German-made metronome features an accurate audible timing system that is easily adjusted via a sliding counterweight. It features precision performance equal to a full size metronome with full tempo range with a strong, reliable wind-up mechanism. The sound is loud enough even for loudest instruments.