【Product Description】: Excerpt Groundbreaking horn training equipment has arrived from Mr. Will Sanders, a professor at the Karlsruhe University of Music!! This item, "Big Buzz," can be attached to a horn for buzzing and breath control practice. The size of the hole in the Big Buzz can be adjusted to your preference. The larger the hole, the more air leaks out, making it harder to produce a sound, which allows you to practice blowing more air into the instrument. After practicing with the hole open, when you remove the Big Buzz and play the horn as usual...! The resonance increases remarkably, allowing you to play naturally. ◇◆◇◆◇◆◇◆◇◆◇◆◇◆◇◆◇◆◇◆◇◆◇◆ I am selling this because I no longer use it. I used it with an Alexander 103. There is some slight rust on the shank, but it does not affect its use at all.