A digital synthesizer which utilizes special processing chips designed to support Casio's Phase distortion synthesis architecture. With full velocity and pressure sensetive keyboard but otherwise it's a CZ-3000 essentially.
Normally pretty reliable machines. Key contacts problems eventually. See the general repair tips for help with this problem if it arises.
I have replacement slider caps that fit the commonly missing CZ series sliders. They have a dished front so they grip better but stick up on the ends more than stock. Here is a photo of CZ5000 with them installed.
American Perfit has parts they say for Casio.
Contact Sound Doctorin'