SpiroFlex SpiroFlex 75 plug (PP) for duct box with gasket ZAT75-PP

The SpiroFlex SpiroFlex 75 plug (PP) is a polypropylene closure designed for installation in duct or junction boxes with an integrated gasket. Intended for round 75 mm openings, this removable plug provides a sealed barrier to prevent dust, debris and uncontrolled air flow in ventilation and HVAC systems. Its gasket interface ensures a tighter fit in boxes that accommodate a gasketed closure, allowing maintenance access while maintaining system cleanliness and airflow integrity.

Advantages

The polypropylene construction delivers chemical resistance and dimensional stability in typical building service conditions, while remaining lightweight and easy to handle during installation. The integrated gasket seating ensures a reliable seal against air leakage and particulate ingress without additional sealants. The removable design allows quick access for inspection, cleaning or modification of ductwork, reducing downtime compared with permanent closures.

Suitable for

• Sealing round 75 mm ventilation or HVAC box openings
• Temporary or removable closure during ductwork installation and maintenance
• Protecting duct interiors from dust and debris on construction sites
• Applications requiring a gasketed, air-tight removable plug

Key specifications

• Material: polypropylene (PP)
• Nominal opening diameter: 75 mm (suitable for round openings)
• Type: removable plug with gasket seating
• Function: dust and air-seal closure for duct/junction boxes
• Installation: press-fit or insert into gasketed box opening

How to use

Verify that the duct or junction box opening is the correct round 75 mm size and that the box includes or is compatible with the intended gasket seating. Align the plug with the opening and press it into place until the gasket contacts the box surface and a secure seal is achieved. For removal, grasp the plug and pull steadily to disengage; if necessary, use a flat tool to release any friction fit carefully to avoid damage to the gasket or surrounding box. Inspect the gasket periodically and replace the plug if the seal becomes compromised.

Usage recommendations

Use the plug in indoor ventilation and HVAC applications within normal temperature ranges for polypropylene. Avoid exposure to prolonged direct sunlight or high-temperature sources that could deform the material. For environments with aggressive chemicals or solvents, confirm chemical compatibility before long-term use. Regular inspection during maintenance is recommended to ensure the gasket remains intact and the closure maintains an effective seal.