The BC model incorporates a second tone generator producing a chorus effect controlled by a single draw bar on the right control panel. There is no foldback at the low end of the manuals, so no bass notes extend down into the pedal range. While it lacks the vibrato/chorus switch of the B3/C3, it has a “Tremulant” control to introduce a simpler tremolo. The Trek II Percussion provides three overtones rather than the standard two on the B3/C3, and allows blending of all three by slide controls. This organ is in working condition. It is only available for local pickup. If shipping is needed, customer must coordinate that.