This is a synthetic reed "VK1" with a strength equivalent to Vandoren's Blue Box (Traditional) size 3. I tried it out, but unfortunately, it didn't suit me, so I'm offering it for sale. **************************** The synthetic reed "VK1" is made of a new composite fiber created by Vandoren after 7 years of research. This new composite fiber doesn't just mimic the structure of cane. It reproduces the essential physical properties of cane to achieve the same acoustics as cane reeds.