The Balu Euphonium Straight Mutes feature the same fiberglass and wood veneer construction as all other Balu Mutes. The euphonium mutes are revolutionary in they offer mute cork in two different thickness that attaches with Velcro, to allow the player to easily adjust the fit of the mute to their instrument. In collaboration of top musicians and artists, Balu Mutes are able to provide some of the world's best mutes, including a Horn practice mute with negligible air resistance. Balu Mutes manufacturers mutes for Horn, Trumpet, Trombone, Euphonium and Tuba.