Vintage Radioshack Concertmate 690 Keyboard (Casio CTK-80) Works Great!

Vintage Radioshack Optimus Concertmate 690 keyboard, an exact copy of the Casio CTK-80, produced in the late 1990's. Tested with 6 AA batteries, and works great, but can be powered with an adapter(not included). Features include: 49 Full Size Keys/4 octave range, 8 note polyphonic, 100 instrument choices / 100 rhythms and auto chord accompaniment. Keyboard is in good shape with only minor cosmetic blemishes including specks of stains on keys, note stickers on keys, some scuff marks on side, and battery compartment was cleaned out as it had battery corrosion but works fine so contacts were not damaged. No output jack or any auxiliary jack except for adapter. A good basic keyboard with its typical range of dated sounds.