A buddy of mine showed me this a few days ago - he purchased it at a local yardsale from a retired power company employee. I have no idea what it is. The insulators have no wire grooves, and they have a threaded insert affixed in their pinhole. The insulators thread onto a piece of all thread, which in turn threads into the bracket...all kept in place with a lock washer. The center of the bracket has a brass point, which appears to have lightning or arc damage. Any ideas?