BIGBUZZ is an American shank. It has only been used a few times and has been stored for a long time. There is some rust, but there is no problem with use. It comes with a case. The following is a quote from DAC's HP: Quote: A groundbreaking horn training tool has arrived from Professor Will Sanders of the Karlsruhe University of Music!! "Big Buzz" is an item that can be attached to a horn to practice buzzing and breathing. Big Buzz allows you to adjust the size of the hole to your liking. The larger the hole, the more air leaks out, making it difficult to play the instrument, and you can practice putting 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 surprisingly, and you can play naturally.