These are pretty cool. My wife wanted a Black Pipe lamp and wanted the Mason Jars to just hang there, bulbs within. She didn't want pipe running to the bulb and no supports. So, we came up with these covers/clamps. The two halves come together within the cap of the jar, and hold fast the light bulb assembly. No glue or any other hardware required! Now, I made them look like gears for her design. They can be made to tailor fit the look you want!
They can also be made for any size jar/bulb socket configuration. Just let us know and we'll work with you and your design ideas.
Our standard size, shown here, which I designed for is the 1 PINT Jar.
(The other random pieces in the background are wire exits for the pipe. They eliminate the wire rub through)