This is a center vent mount for a 52mm boost gauge to fit the interior of a 08-13 WRX and STI.
All you have to do for fitment is to remove the horizontal and vertical vent pieces from the right side. There is also a little plate that the vertical pieces of the vent sit on, this needs to come out also, push the printed piece in. I drilled 2 holes in the top of the vent so I could use a cable tie in addition with the provided mounting hardware for fitment.
If your car is left hand drive, obviously you can just mirror the stl in your slicer and use the left center vent