I was presented this Clough-Brengle model OC at the 2004 CC-AWA Annual Conference in Charlotte, NC by Imre Vanyi from Atlanta.
This appears to be a early version of the model OC since it does not have the leather handle or the frequency chart on top as some other examples have.
This unit appears to be 100% original, I don't think it had ever been opened up before I got it. It still has all the original components. I cleaned the outside of the cabinet and replaced the plastic window material that had yellowed to the point of not being clear anymore. After cleaning the cabinet I recolored the original black crackle paint.