12"w X 12"h [Duct Opening] 3-Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 13.75"W X 13.75"H] Aluminum Adjustable Curved Blade actual front end outer dimensions Ducting Components RG2016 FBA-HP Applications The C box

actual front end outer dimensions are approximately 30 5/8" width X 18 5/8" height

+ Product Details Size - 6"w X 28"h is the size for the duct opening measurement only

background-color: #5296DD

Actual Filter Size – 27 3/4"w x 25 3/4" x 1"

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

12"w X 12"h [Duct Opening] 3 Way Fixed Curved Blade Air Supply Diffuser Register Vent Cover Grille [Outer Dimensions: 13.75"W X 13.75"H] Aluminum Adjustable Curved Blade actual front end outer dimensions Ducting Components RG2016 FBA HP Applications The C box actual front end outer dimensions are approximately 30 5 8" width X 18 5 8" height + Product Details Size 6"w X 28"h is the size for the duct opening measurement only