New versatile American-style oboes for comfortable playing The globally popular 441 series has been renewed with additional keys and features to increase comfortability in performance. One addition is the third octave key as indicated by the new series name "441T." This improvement enables players to perform without stress or difficulty. Duet+ upper joint Duet+ is a patented technology of Yamaha. The wooden inner bore and tone holes are coated with ABS resin. This prevents moisture from soaking into the body, making it durable despite changes in temperature or humidity. It is designed to preserve as much as 90% of the wooden portion, preserving the oboe’s sound and resonance.