Double Horn in F/Bb. Perhaps the most-played "large throated" horn in the world. Recording artists, major orchestra horn players and premier soloists have made the Conn 8D their exclusive choice. Their reasons? Tone color, response, intonation and volume. • All nickel silver construction with lacquer finish • Change valve located before the valve cluster • 0.486" (11.89mm) bore • 12.25" (311mm) large throat bell • Tapered rotors & bearings • Fully mechanical change valve • Adjustable levers • Conn 7BW mouthpiece • Conn 7514L deluxe hardshell case