12" x 4" Adjustable Blade Sidewall Ceiling Register Vent Cover Diffuser Heavy Duty Stamped Steel (Listed Size is for Duct Opening or Inside Measurement) actual outside dimension is 14

actual outside dimension is 14

actual outside dimension is 11

and lay-in ceilings

•The Listed size 10"x 6" is for inside duct opening measurement

Actual outside measurement is 10" x 8"

12" x 4" Adjustable Blade Sidewall Ceiling Register Vent Cover Diffuser Heavy Duty Stamped Steel (Listed Size is for Duct Opening or Inside Measurement) actual outside dimension is 14First thing to know about size selection: take the vent cover off the wall or ceiling. Measure the duct opening where the vent can fit in. Use the measurement to determine right size to buy. This product has listed size 12w X 4h is for duct opening measurement only, actual outsize overall dimensions is 14 wide by 6 high. If your duct opening size is 12 x 4, this is the right size and will fit in well. If you measure outside or surface size, you will