airRoxy pipe reducer 120–125 mm model 02-230 by airRoxy

airRoxy pipe reducer 120–125 mm model 02-230 by airRoxy is a ventilation accessory designed to provide a secure mechanical transition between a 125 mm and a 120 mm duct. Made for ventilation systems, exhausts and air distribution lines, this reducer enables a tight fit where a slight change of diameter is required. Constructed to meet common HVAC installation needs, it is intended for use in residential and light commercial applications.

Advantages

The reducer provides a reliable, low-profile connection that reduces air leakage at the join between two different pipe diameters. Its geometry ensures concentric alignment of ducts and supports straightforward installation without complex tools. The component is compatible with standard circular ventilation ducts and facilitates consistent airflow by minimizing abrupt transitions. Manufactured by a specialist ventilation brand, the reducer is designed for durability in indoor HVAC environments.

Suitable for

• Connecting a 125 mm duct to a 120 mm duct in ventilation systems
• Adapting exhaust outlets to slightly smaller intake or discharge pipes
• Residential HVAC and light commercial ducting where small diameter changes occur
• Air distribution branches and retrofit adjustments in existing ductwork

Key specifications

• Input/outlet diameters: adapts 125 mm to 120 mm
• Type: concentric circular pipe reducer for ventilation
• Intended use: indoor HVAC, exhaust and air distribution systems
• Compatibility: standard round ventilation ducts of corresponding diameters
• Mounting: mechanical push-fit or clamp attachment depending on duct type

How to use

Measure the duct diameters to confirm compatibility with the 125 mm and 120 mm sizes before installation. Slide the appropriate ends of the reducer onto the matching ducts, ensuring concentric alignment and full seating. Secure the connection using the method appropriate for the duct material and site practice — for example, a sheet-metal clamp, hose clamp, or pop rivets for metal ducts, or a suitable mastic or tape for flexible ducts. Check for proper airflow and seal after installation.

Usage recommendations

For best performance, ensure both duct ends are clean and free of sharp edges before fitting. Use compatible clamps or sealing materials rated for HVAC use to minimize air leakage. Avoid using the reducer outdoors unless the material and finishing are verified for external exposure.