I have not been able to find the exact model number or name of this telephone. There is very little information about it on the internet. For a long time I did not even know who the maker was, even though I did ask around. When I got it, it was clear that it was not made by Ericsson, although at a first glance it could be mistaken for an Ericsson DE500. It did not have any makers mark on it.
I bought it, because it had a replacement handset on it I needed for another project. It was a German handset, that was clearly wrong for this model.
I had a hunch it could be made by ATEA, but after some asking around it turned out that was not the case.
After some years I came across an article on the above mentioned telephone company which had a picture of this phone. That is the only thing I could find about it. It did not state the model number or name of this model. The article also states that it is a rebranded DE500, but that is certainly not the case. Apart from some screws there are no compatible or interchangeable components. It is definitely a different design.
The FT&T factory was situated in Buffalo, New York. It was next to what was then an LM Ericsson factory. Apparently FT&T bought a lot of components from Ericsson and many of their designs drew inspiration from Ericsson models, which explains the resemblance of this phone with that Ericsson model.
As mentioned above the phone had a German handset on it when I got it. I replaced it with a standard Ericsson handset. It turned out to be a good choice as the original handset, according to the picture I found, was indeed of that model or very very similar.
This phone has since then left my collection, as it did not really fit in because it is not a dial phone. I sold it to somebody in Spain. Coincidentally after a few years somebody else from Spain contacted me about this model and it turned out he acquired the very same phone.