PATIKIL 2Pcs 5" Round Duct Access Door, Duct Maintenance Access Door Galvanized Steel Ducting Cover with Rubber Gasket Adjustable Knobs for HVAC Duct Inspection, Silver. Designed with two panels, equipped with rubber gasket and adjustable knobs, providing an airtight seal around duct openings and easy entry into air ducting for maintenance.
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