12"W X 12"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 13.75"W X 13.75"H] 18" Round Duct Pipe It has an outer surface

It has an outer surface made of high-quality aluminum foil and an inner surface made of metalized PET with inside high-tensile spring steel wire

+ Product Details Size – 12"w X 24"h is the size for the duct opening measurement only

Actual Front End Outer Dimensions Are 14" Width X 6" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

+ Product Spec Sheet Return Air Grille Spec Sheet

+ Product Details Size - 12"w X 18"h is the size for the duct opening measurement only

12"W X 12"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 13.75"W X 13.75"H] 18" Round Duct Pipe It has an outer surface+ Product Details Size 12"w X 12"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 13. 75" width X 13. 75" height. Design Easy unrestricted airflow for your HVAC system 50 angled to provide maximum airflow. High Quality Solid stamped steel with counter sunk screw holes (screws included) and no sharp edges. Powder Coat Finish Smooth, shiny, scratch resistant, beautiful. Looks like it was just