I'm a flute player and I bought this flute sometime ago and I'd like to know:
Flute Yamaha 371 Allegro version
What kind of passage I may use this Key and What's the name of this Key?
Please, I'd like the references or a comment of a recognized flute player or some article with the example.
Edited:
I found the name of the key the the manufacturer's website. They call it the Ice lever (A#).
Can you give me an example of how the Ice lever is used in practice?
I'm accustomed to using alternative keys depending the passages on the music sheet, but this key doesn't make sense because B flat is very near to this key.
The key:
The hole that key close: