●This is a mute for Violin Viola viola playing that is used by hanging on a tailpiece ●It can be used to reduce the volume and practice. It is also recommended for night practice or indoor play. *This is not a completely silent item ●Single hole for violin violin viola width approx. 0.6 inch (16 mm), height approx. 0.8 inch (21 mm), thickness approx. 0.2 - 0.3 inch (5 - 8 mm) ●Made of rubber that is easy to handle even for beginners. Can be attached to your instrument even when not in use ●It is less likely to damage your instrument, so you can use it with confidence