This wind-up metronome is a precision-made piece of machinery. It is spring driven (no battery required!), and comes with a protective face cover as well as a removable winding key. Measuring only 2 inches deep, 1 inch wide, and 4 inches high, this metronome is portable, and will fit inside nearly any instrument case or music bag.

The tempo range is from 40 beats per minute to 208 beats per minute.
Precision Compact Metronome from Wittner