... 1. Mechanical Metronome 2. Loud sound 3. Stable Metronome 4. Robust structure Stable musical instruments · Metal mechanical core,pure metal movement ... · Accurate beat with bell,stable, loud · Bell for beats 0, 2, 3, 4 and ... one box: 10PCS·Other:retia outside, brightness, high-grade, stable,tower and beautiful shape ·Colors:wide choice of colorsThis metronome ...