8" x 8" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling w14h14 Actual Filter Size – 13

Actual Filter Size – 13 3/4"w x 7 3/4" x 1"

Actual Filter Size – 29 3/4"w x 11 3/4" x 1"

+ Product Details Size - 28"w X 12"h is the size for the duct opening measurement only

1/2" White insulation will give you a good R value of 3

Actual Filter Size – 23 3/4"w x 21 3/4" x 1"

8" x 8" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling w14h14 Actual Filter Size – 13+ Product Details Size 8"w X 8"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 9. 875" width X 10" height. High Quality High quality steel construction, no scuff powder coat durable finish, smooth, shiny, scratch resistant, no sharp edges, 2 recessed screw holes on each side with screws included, screws same color as vent cover, easy installation. Adjustable airflow control Adjustable airflow