A mute, also called sordino, refers to a device made of wood, synthetic material or metal that weighs down the upper part of the bridge to cause it be more sluggish. The result is a more quiet and nasal tone that composers use for certain effects (con sordino). In day-to-day concert use, an easily attachable mute made of synthetic material has become most popular. When it is not in use, it can easily be stored between the middle strings. There are several different models and forms.