The Artisan Trombone Collection is one of the most exciting developments in Bach Stradivarius professional trombones. The A47 is completely modular allowing each player to customize the Artisan trombone to meet their own playing needs. It features the "Infinity" axial flow valve. This patented valve design eliminates the metal-to-metal contact found in any other axial flow design through the use of sealed bearings both in the nose and in the back plate. This assures tight tolerances that will resist wear over time. The 8½" one-piece hand-hammered yellow brass Bach Artisan will define the symphonic sound for generations. The .547" large bore combined with the patented "Infinity" valve and open wrap F attachment offers a warm sound, great projection, and an efficient and open feel. The reverse main tuning slide construction offers an more open response. The chrome plated nickel silver inner handslide tubes provide the ideal surface for smooth and quick hand slide action. The clear lacquer finish adds a subtle warmth to the sound overall. The Bach Stradivarius A47I professional trombone is ideal for both symphonic and solo performance.