the metal inlet pipe on the back appears to be slightly tapered. In order to install on a 2.1" thick wood floor, I used an extender, but in order to fit the extender in the available space, I had to cut off the metal inlet pipe a bit. After I cut it, its diameter was too large to fit the extender, so then I cut slots in the cutoff inlet pipe to get it to bend outward and fit, and then applied silicone sealer to seal up the slots.
screws were not long enough to reach installed receptacle. Had to purchase different screws for anchoring and could not find good match to cover plate.
It looks very nice, but it was a bit more costly than I originally anticipated.