This guitar mechanical metronome fine workmanship made of high toughness PPS material it ca last for a long time. It is mechanical you can use it without using any battery it is accurate and the vintage wooden pattern is beautiful. The unique groove design makes it no need to add lube and makes it not easy to be worn. The beats can be easily adjusted from 2 to 6 which can meet your different needs. Fit for using with panio guitar violin and more is a good tool for musician and instrument beginner. Specification: Material: PPS. Color: Show as picture. Size: 21*11.5*11.5cm. There might be a bit color distortions due to different computer resolutions. There might be a slight errors due to different hand measurement. 1* Metronome.