Interface Outer Diameter: 73 mm / 2.9 inch; Diagonal Mounting Hole Distance: 88 mm / 3.5 inch; Distance Between Adjacent Mounting Holes: 43 mm / 1.7 inch; Base Outer Diameter: 98 mm / 3.9 inch; Color: Grey; Material: Galvanized Iron, Stainless Steel; Packing List: 1 x Duct Connector, 1 x Stainless Steel ClampAdvantages: 1. The connector is made of galvanized iron, which is anti-corrosion, cold-resistant, high-temperature resistant, not easily deformed, and durable. 2. The base of the connector has screw mounting holes, no drilling is required, and it is directly fixed on the wall with screws, which is easy to use. 3. There are stainless steel clamps in the package, which is convenient for fixing the air duct flange and is not easy to deform and move.
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