16" X 16" Sound Rated Steel Access Panel Felt Covered Door For Concealed Wall / Ceiling Application With Slotted Lock - [Outer Dimensions: 17" Width X 17" Height] w20h20 + Product Details Size –

+ Product Details Size – 20"w X 30"h is the size for the duct opening measurement only

+ Product Details Size - 40"w X 16"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 34 5/8" width X 38 5/8" height

this flex duct decreases the pressure loss and provides a more hygienic environment

Filter Size - 21

16" X 16" Sound Rated Steel Access Panel Felt Covered Door For Concealed Wall / Ceiling Application With Slotted Lock - [Outer Dimensions: 17" Width X 17" Height] w20h20 + Product Details Size –+ Product Details Size 16" X 16" is the size for the drywall opening measurement only, actual front end outer dimensions are 17" Width X 17" Height High Quality High grade steel construction. Design 1mm galvanized steel material with sleek, shiny, durable white powder coat finish for an attractive look & high durability corrosion protection 15mm medium density fibreboard with felt cover and rubber sealing between the door and frame for tight security.