14" X 14" [Duct Opening] 4-Way Air Vent Adjustable Aluminum Curved Blades Integral Multi-Shutter Damper HVAC Diffuser [Outer Dimensions: 15.75"W X 15.75"H] Filter Grille Actual Filter Size – 21 Height_16in RG1612AL Product Details Size 14

Actual Filter Size – 21 3/4"w x 35 3/4" x 1"

or commercial environment

+ Product Details Size – 24"w X 6"h is the size for the duct opening measurement only

+ Product Details Size - 30"w X 30"h X 2"d (for duct opening measurement only)

Its locking eight-tumbler mechanism and supplied key safeguard your thermostat from tampering

14" X 14" [Duct Opening] 4 Way Air Vent Adjustable Aluminum Curved Blades Integral Multi Shutter Damper HVAC Diffuser [Outer Dimensions: 15.75"W X 15.75"H] Filter Grille Actual Filter Size – 21 Height_16in RG1612AL Product Details Size 14 Actual Filter Size – 21 3 4"w x 35 3 4" x 1" or commercial environment