Here is a wonderful early electric bottle brush tree. This has a heavy duty cardboard cone inside with plastic light inserts. (shown) The light source comes from the ceramic base and the bulb. The advantage of this old tree, compared to ones in which the bulbs themselves light, is that it will always work, as long as there is a bulb in the base. It operates in a similar way to the 1970s ceramic trees, which also have their light source in the base.
This measures approx 15 inches high, including the base. The evergreen is still a vibrant color of green, as it has been carefully stored over decades. I believe the maker is Glolite, Made in USA, but I am not 100% certain, as often manufacturers copied one another. I say Glolite because I own a similar tree in white, with the original box.
This is guaranteed to be old, original and somewhat rare in this condition.