Features: Universal Mechanical Metronome:This universal mechanical metronome is suitable for most musical instruments such as guitar bass piano violin drum etc. Great Assistant for Musical Instrument Practice:Accurate rhythm clear and loud sound for helping you improve your sense of beat and tempo suitable for musical instrument beginners. Easy to Use:Wind it up first then your desired beat(2/3/4/6/0) and tempo(40-208 bpm) finally remove cover and set pendulum in motion. You can slide up or down weight on pendulum rod to adjust speed according to meter plate. Eco-friendly Mechanical Energy:No battery or extra is needed; adopts a winding mechanism for to produce metrical . Compact and Design:Traditional pyramid shape design durable ABS body with a transparent conservation cover portable and safe to transport. Specifications: Color: Black Material: ABS + Metal : 2/3/4/6/0 Tempo: 40-208 bpm Item Size: 9.5 * 12 * 20.5cm/ 3.7 * 4.7 * 8.1in Item Weight: 430g/ 15.2oz Package Size: 24 * 12.5 * 11cm/ 9.4 * 4.9 * 4.3in Package Weight: 545g/ 19.2oz Note: Please pull out brake on bottom before using metronome. Package List: 1 * Metronome 1 * Users Manual(English & Chinese)