"Found this metal item in my junk drawer. The top “screw” is hollow and screws into the bullet-looking thing. Penny for scale."
A: "I think this is part of a cable display system.
Bit on the right – that gets screwed to a wall or ceiling, with the screw coming out of the hole closest to us in your picture.
Bit on the left – the wire goes though the hole at the bottom, and is then crimped off so it cant fall out. The entire body then screws onto the ‘bit on the right’ and the two holes in the side are to take up tension."
The new guy laid that brick.