6" X 6" Sound Rated Steel Access Panel Felt Covered Door For Concealed Wall / Ceiling Application With Slotted Lock - [Outer Dimensions: 7" Width X 7" Height] w36h36 + Product Details Size -

+ Product Details Size - 36"w X 24"h is the size for the duct opening measurement only

But they are also the most visible representation of you air system

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6" X 6" Sound Rated Steel Access Panel Felt Covered Door For Concealed Wall / Ceiling Application With Slotted Lock - [Outer Dimensions: 7" Width X 7" Height] w36h36 + Product Details Size -+ Product Details Size 6" X 6" is the size for the drywall opening measurement only, actual front end outer dimensions are 7" Width X 7" 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.