Serial #0250. Excellent example of this classic two voice synth. No sequencer on this one. Clean mods were added to this in it's past for the additional controls on the back: CV 1 IN Gate 1 IN Filter 1 IN Filter 2 IN There are also two switches added to the front panel to enable/disable SEM 1 and SEM 2 completely. Also a mod to patch SEM1 into filter of SEM2 This synth sounds amazing and has just been inspected and all pots switches and keyboard contacts expertly cleaned, calibrated, and serviced [including jwires and buss bar] by a qualified pro audio technician. Oscillators correctly scaled also.