Features: User-defined Timer: support the custom time of 1-90 minute zone tone which is more convenient to formulate scientific practice time for children and help them form good habits. 9 Rhythms & 8 Sounds: including human voice and mechanical beat etc. which help children to practice level changes and add interest. User-friendly Design: 2.1-inch LCD display screen LED indicators easy-to-adjust control buttons and knobs type-c charging interface and earphone jack the light weight solid voice metronome is simple to use and easy to carry. Cute Robot Shape Design: having a dynamic and futuristic style shape the cartoon robot metronome specially designed for children. Precise Rhythm & Full Timbre: it has a horn cavity the timbre is natural real and full which is conducive to protecting children s hearing. Battery Operated: powered by a 3.7V 500mAh rechargeable lithium battery it can be used continuously for more than 6 hours even in the maximum mode. Power Saving Function: the metronome will automatically shut down after not working for more than 10 minutes. Wide Application: common to all instruments such as piano guitar drum set zither etc. Specifications: Color: White / Mocha Green / Pink (Optional) Material: ABS Beat: 0 1 2 3 4 5 6 7 8 9 Tempo: 30~250bpm Metronome s Tone: Voice mechanical metronome etc 8 in all Countdown : 1~90 minutes Power Supply: DC 5V Type-c Rated Power: 2.5W Battery: Built-in 3.7V 500mAh lithium battery Item Size: 105 * 83 * 80mm / 4.13 * 3.26 * 3.15in Item Weight: 119g / 4.21oz Package Weight: 200g / 7.07oz Package Size: 12 * 9.5 * 9cm / 4.72 * 3.54 * 3.74in Packing List: 1 * Metronome 1 * Type-C Cable 1 * Manual (English)