.459" medium-large bore, 4-3/4" two-piece bell with rim wire, Monel metal pistons with one-point nylon valve guides and enclosed barrel-shaped bronze valve springs, one-piece brass valve casing, first valve slide thumb hook, adjustable third valve slide finger ring and stop mechanism, two waterkeys, nickel silver mouthpiece receiver and trim, brass turning slide receivers,silver plated finish, genuine Vincent Bach mouthpiece, double-wall case.