12" x 12" [Duct Opening] Ceiling Supply Diffuser Vent Cover – 4-Way Airflow with Full Aluminum Frame, Back Blades & Opposing Blade Lever Damper [Outer Size: 15" x 15"] R-6.0 insulation + Product Details Size -

+ Product Details Size - 18"w X 28"h is the size for the duct opening measurement only

+ Product Description Upgrade your ventilation with our premium grilles and registers

It also has a slot for cutting PVC pipes of up to 12mm (approx

+ Product Details Size - The listed 6" diameter refers specifically to the size of the duct opening

} + Product Details Size & Compatibility - The size of a boot register end is 14" X 4" X 7" galvanized floor boot end center 26-gauge

12" x 12" [Duct Opening] Ceiling Supply Diffuser Vent Cover – 4-Way Airflow with Full Aluminum Frame, Back Blades & Opposing Blade Lever Damper [Outer Size: 15" x 15"] R-6.0 insulation + Product Details Size -+ Product Details Size Refers to duct opening only. The face frame extends roughly 1. 5" on each side. Do not measure the overall grille for sizing. Design All aluminum frame and back blades. Rustproof and built to last in moisture prone environments. Quiet Airflow Opposing blade damper design reduces vibration and noise for smoother air distribution. Clean Finish White powder coated surface resists chips, scratches, and discoloration over time. Easy