Mounting Electrical Box Between Studs
Electrical boxes typically are mounted to the sides of studs for stability. Whether nailed to the studs or screwed in with adjustable brackets, boxes on studs tend to stay in place for a long time.
But sometimes, it’s not always possible to find a suitable mounting point against the studs. What about between the studs?
Using old-work electrical boxes is one way to hover the boxes between studs. Old-work boxes attach directly to the drywall, not to the studs.
After cutting a rectangular hole in the drywall, you insert the electrical box in the hole. Then, with either a manual Phillips screwdriver or a cordless drill/driver, you turn the two screws clockwise.
Turning the screws also turns the two plastic wings behind the drywall, forcing the box against the drywall. While it’s not as strong as a stud-mounted box and sometimes the wings will break off, often it’s the only option when you want the box to be between studs.
Source: The Spruce