Yamaha YOB-441M Duet+ Intermediate OboeYamaha oboes achieve a clear sound quality and superb intonation by dramatically improving the precision and stability of the bore. Also to cope with various durability issues inherent in wooden wind instruments, Duet+ models employ innovative techniques to form a protective layer next to the air column. The combination of precious wood and state of the art resin is not simply a "Duet" of tradition and technology it's a "Plus" advantage indeed! Silver