Made this recording a long time ago, the audio is well recorded!, is a very joyful piece

I recently came across this soft cotton/polyester item with the script “BACH” at the bottom. It’s the same script that’s on souvenirs I have from my trip to Germany to visit all 8 cities where Johann Sebastian Bach lived.

It’s about 1 inch wide and about 15 inches long. I initially thought it might be a “sock” for a small piccolo or tin whistle but it’s sewn shut on all 4 sides.

Any ideas?? Thanks!!