none scratch to your violin / Cello, none damage to bridge, better than metal type.It can reduce the overtones produced by the strings, give the violin / Cello a smoother, more mellow sound Application: Suitable for violin or cello You just need to put the mute on top of bridge, very Great for you to use when you want to practice playing violin / Cello, but don ' t want to disturb others Each light weight and small, easy to store and carry anywheres