Made for a 4" x 12" Duct Opening - Item Dimensions are 5 1/4" x 13 1/2" POP UP AIR DIVERTER - Easily pop up deflector to direct air from under furniture, away from wall and create better air flow for both heat and AC CONVENTIONAL COVER and DEFLECTOR - Can be used as a normal floor register or pop up to divert air CEILING and FLOOR - Knockout holes at each end for ceiling installation High Impact Construction - Made of high impact polystyrene for walk on design Hartford Ventilation Pop Up Floor Vent Register - 4” x 12”(Duct Opening) is the perfect solution for redirecting both heat and AC. The deflector can be both a convention floor register or when needed can pop up to direct air. Whether under the couch, cabinetry or other furniture you can pop up the deflector and angle the air direction needed. The pop floor register makes for a more comfortable room with more consistent air temperature. Actual dimensions are 5 1/4" x 13 1/2".