This Jo-Ral Bucket mute is designed for tenor trombones with a 7"-8" bell. The hand spum aluminum construction makes this mute both light and durable. This Bucket fits inside the bell as opposed to the traditional clip-on styles. This fascilitates easier mute changes and decreases the chances of scratching your bell flare. The tone of this mute can be changed by subtracting or adding the cotton material inside.