Access door to inspect and maintain circular ventilation ducts


  • Inexpensive curved access door
  • Polyamid knobs ensure a quick removal/re-installation of the door without the need for any tools
  • Shape allows the back plate to be passed through the duct openings, and the neoprene gasket on the back plate
  • Strengthening ribs, galvanized steel spring, zinc plated volt, with neoprene gasket on the back plate for a tight seal
  • Grants easy access into sheet metal ductwork systems for resetting dampers, cleaning filters, or regular maintenance

Model Duct Size (in.) A B
CAD 200

3" to 4"

8-15/16" (226mm) 4-9/16" (117mm)
CAD 250

6" to 8"

11-1/16" (280mm) 6-1/2" (166mm)
CAD 300 10" to 12" 13-3/16" (333mm) 8-13/16" (221mm)
  1. Stick self-adhesive template onto duct (a template is provided with each door)
  2. Cut out aperture (there is a tolerance of +3 mm)
  3. Install door by unscrewing the hand knobs until thread is level with top of bolt.
    Using both hands, place the door in the hole at an angle, turn straight and pull out slightly to align.
    Then tighten the knobs

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