The Olympus Pen EE-3 was one of the last of the Pen series half frame cameras produced by Olympus. It was in production from 1973 to 1986. In terms of features it seems almost entirely indistinguishable from the EE-2 that came before it. ISO settings go from 25 to 400 and it also can be used in a manual aperture mode with a flash. There is no focusing mechanism.
This particular camera appeared to have some light leaks when I first got it but I’ve replaced the light seals and am currently running another roll through it with high hopes. The other Pen I have seems to have problems with frequent exposure failures but this one is in better condition in that regard.
The new light seals seem to have done the trick. Here are some photos from this camera.