This is a typical junctionbox for a certain style of european outdoor lightning. They often break, get lost, or the screws that attach on the outside break. Note also that the small part is a grommet for the cable to pass through. It adds some waterproofing and needs to printed in flexible filament.

This model imitates them but relies on normal, external wooden screws that screw into the wall behind the lamp. If you have some kind of masonry use screw plugs.

Pro tip: Poke a hole through the grommet using either the peeled cable parts or a sharp screw driver for an easier time. Then press into the hole. It should self-lock to some extent.

Print settings mainbody: Print in flame retardant filament. 5 walls, top and bottom layers 15% infill No supports

Print settings Grommet: Print in TPU 3 walls, top and bottom layers

V2 released: 2026-04-08 Change log: Higher tolerance for ease of mounting. Old ones could be a tight fit occasionally. Added a fillet at the primary mounting point to the walls for sturdiness.

V1 released: 2026-03-29