Designed and shaped for large bore horns, especially the Conn 8-D, the # 24 is in essence an elongated # 5.Trumcor French Horn MutesTrumCor mutes are carefully handcrafted with wood and a specially formulated resonant fiber material. They create a muted tone that is vibrant, warm and responsive. These mutes are durable, and the wide selection of sizes ensures a proper fit and excellent intonation. TrumCor mutes produce a beautiful sound, and at the same time preserve the unique timbre of the horn in all registers and at all dynamics.