The Bach 42B Stradivarius trombone features an F attachment with a standard valve and wrap. Its one-piece hand-hammered bell offers increased resonance with a large symphonic sound that projects without distortion. 8.5" one piece yellow brass bell. .547" large bore. Chrome-plated nickel silver seamless inner slide. Brass outer slide. Nickel silver handgrip. Traditional rotor valve with closed wrap tubing.