20" X 20" Sound Rated Steel Access Panel Felt Covered Door For Concealed Wall / Ceiling Application With Slotted Lock - [Outer Dimensions: 21" Width X 21" Height] Grille + Product Details Size –

+ Product Details Size – 20"w X 24"h is the size for the duct opening measurement only

+ Product Details Size - 26"w X 36"h X 2"d (for duct opening measurement only)

the actual front end outer dimensions are 7" in diameter

+ Product Details Size – 14"w X 6"h is the size for the duct opening measurement only

20" X 20" Sound Rated Steel Access Panel Felt Covered Door For Concealed Wall / Ceiling Application With Slotted Lock - [Outer Dimensions: 21" Width X 21" Height] Grille + Product Details Size –+ Product Details Size 20" X 20" is the size for the drywall opening measurement only, actual front end outer dimensions are 21" Width X 21" 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.