Hello, and thank you to everyone for all this information. When I plugged the head in, the light seemed to be a sharp/acid-y green. I don't have a darkroom at the moment to run a test print, but wanted to get everything in place (whatever filters I might need) and all, so that I can use light head. Louise mentioned counting the coils of the bulb -- there are 9 by my count --which she said indicates a high intensity bulb. There is no low/high switch. I'm getting closer but still am not sure what I've got here, sounds like a V54...