Key of Bb. With quick response and superb intonation, this model provides professional features for players at all levels. .462" (11.73mm) bore, 4-7/8" (124mm) yellow brass bell, rose brass leadpipe, nickel plated pistons, first slide thumb saddle, third slide with adjustable stop, lyre holder, original King 7C mouthpiece and advanced woodshell case. Full warranty.