8" X 25' - Round Duct Sheet Metal Pipe [5 pcs 5'] 8" Diameter + Product Details Size -

+ Product Details Size - 36"w X 4"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 32 5/8" width X 28 5/8" height

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 20" OR 20" x 18" duct opening (measured at the opening)

Actual Filter Size – 27 3/4"w x 33 3/4" x 1"

8" X 25' - Round Duct Sheet Metal Pipe [5 pcs 5'] 8" Diameter + Product Details Size -8" X 25' Round Duct Sheet Metal Pipe 5 PACK of 5' pipes 30 Gauge Galvanized Crimped End Connection 5 IN A PACK 8 Inch Diameter Pipe 25 Foot Length When Connected 30 Gauge Thick & Made of Thick & Durable Galvanized Sheet Metal Used For HVAC System Duct Work In Any Building or Home In Any Building or HomeIn Any Building or HomeIn Any Building or HomeIn Any Building or Home HIGH QUALITY High Quality Galvanized Sheet Metal with Crimped Ends (Snap Lock