The Artino Rubber Coated Heavy Metal Practice Mute for Violin & Viola is a traditional heavy metal mute with a durable rubber coating. * This rubber coating is designed to protect your bridge and instrument. * As with other heavy metal mutes, it allows for practice without disturbing others and with the rubber coating it reduces the sound level to a minimum while maintaining sound quality. * It takes seconds to fit it on the bridge and is one of the best practice mutes we"ve found. * This model is for violins and violas.