Adds 3mm of additional space if you have a slightly larger capacitor/didn't solder down the transistors and leds fully, used thicker tape/larger battery holder or in my case the DIP socket was causing too much height.
Retains original bottom housing so go download the bottom part here https://www.printables.com/model/46055-tv-b-gone-kit-snap-together-case-aa-version/files
The author remixed this model.