This item was purchased new for around 34,000 yen at a musical instrument store in Tokyo and has been used for only a few days. KF-1 B Vandoren 5RV Lyre, 441-442 Hz type The KF series was developed based on the passion and experience of clarinetist Kazuo Fujii. Born from years of research and trial and error, based on the existing Gleichweit mouthpiece, it offers stable tone, good response, and comfortable playability. The three models (KF-1, KF-2, and KF-3) are highly supported by clarinetists in Japan.