Turns out this was not the manual i was looking for. The concertmate 670 keyboard i have is a "Realistic" model made for Radio Shack and none of the diagrams on the owners manual i received matches up. HOWEVER, I must say the service Owners Manual provides was fast and efficient by being available online. The manual was in good readable condition and easily downloaded.
Thank´s for your help, I already recived these manual from you
Text excerpt from page 22 (click to view)
Nettoyage et entretien
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Attention ! Les produits de nettoyage agressifs ou abrasifs endommagent l�appareil. Nettoyez l�appareil avec de l�eau et de la lessive. Attention ! Les restes de produits de nettoyage endommagent l�appareil. Nettoyez les restes avec de l�eau et un produit de nettoyage.