Features: The mechanical metronome provides beat type selection (0, 2, 3, 4, 6), and beat speed control (40-208beats/min). No battery required, what you need to do is rotating the knob clockwise to wind the metronome. Metal movement ensures stable performance. Detachable cover to protect the inner; sliding weight to adjust the beat speed; pull rod to select the beat type. With transparent shell and metal internal structure, it not only a metronome, but also an ornament for your home. A reliable practice partner for music lovers who play guitar, piano, violin, drum, guzheng and more. Wonderful gift choice. Note: 1. Place it on flat surface. 2. Do not force the pendulum to return to the center position if it's not vertical, please turn the winding key slightly to reset in motion. 3. After using, please put the pendulum in the hook and install the detachable cover. 4. It's not waterproof. Please do not use it in humid or dusty places. Clean it with a soft dry cloth. 5. Do not remove the parts from the metronome, such as the sliding weight, beat selector and so on. 6. Size and color may be slightly different due to manual measurement and different light conditions. Thanks for understanding. Specifications: Color: Transparent Blue/ Transparent Red/ Transparent Purple (Optional) Material: Plastic + Metal Beat: 0, 2, 3, 4, 6 Tempo: 40-208Beats/minute Item Size: 207 * 120 * 103mm / 8.15 * 4.72 * 4.06in Item Weight: 480g / 1.06lbs Package Size: 23.4 * 13.5 * 12.5cm / 9.21 * 5.31 * 4.92in Package Weight: 594g / 1.31lbs Package List: 1 * Metronome 1 * User Manual (English)