It features 32 mini keys for portability and ease of use. The keyboard was sold with a ROM pack (RO-551) that contained music to be used with a "melody guide" training feature to help users learn to play. Manufactured in the late 1980s, it is a sought-after model for its unique vintage sound and potential for circuit bending modifications. It can be powered by five AA batteries or an AC adapter. in original box ( bit of damage to the bix as seen on pictures) fully working, batteries and charger included
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