18" X 14" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling w30h30 + Product Details Size - SV2414 HP Product Details Perfect Fit 12" Round Duct Pipe

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

Actual Filter Size – 33 3/4"w x 21 3/4" x 1"

actual front end outer dimensions are approximately 26 5/8" width X 10 5/8" height -

Please check the measuring guide to ensure a proper fit

ISO Supply Diffusers perform efficiently with air loadings of 6 to 30 air changes per hour (based on 10 ft

18" X 14" ADJUSTABLE AIR SUPPLY DIFFUSER HVAC Vent Duct Cover Sidewall or Ceiling w30h30 + Product Details Size SV2414 HP Product Details Perfect Fit 12" Round Duct Pipe + Product Details Size 28"w X 18"h is the size for the duct opening measurement only Actual Filter Size – 33 3 4"w x 21 3 4" x 1"