My Father's Benrus Watch

In going through my father's things, I found a Benrus Three Star self-winding watch. I'm guessing it's from the 1930's or '40's. I'm trying to find out what the watch is and, of course, if there's any value in it. I'm not looking for a formal appraisal just a ball park as I don't plan on selling it. I'm just trying to document it as much as I can.
I've attached photos showing the face with blemishes, the back with watch number the descriptive words engraved and the crack in the edge of the crystal in the 6 to 8 area.
However, IT DOES RUN and keeps good time. Also, you can hear the self winding mechanism moving.
I'd appreciate anything you can tell me or any advice you have.