AIR Flow Products Air Flow Meters

Overview

The AIR FLOW PRODUCTS RE065 is a duct reducer-increaser fitting designed to transition between 6-inch and 5-inch round ductwork sections. This type of fitting is used to step duct diameter up or down within a supply or return air system, maintaining airflow continuity where duct sizes change. Licensed sheet metal mechanics and HVAC installers work with fittings like this during new construction trunk-and-branch layouts and retrofit modifications. The RE065 is a compact, purpose-built transition piece that seats into standard round duct connections at both ends. The RE065 is suited for residential and light commercial HVAC duct systems where a 6-inch-to-5-inch diameter transition is required. Common install scenarios include branch takeoff adjustments, equipment replacement where duct sizing does not match the new unit's collar, and system rebalancing work. This fitting allows the installer to reduce or increase duct diameter within a single piece rather than using multiple fittings, keeping transitions clean and minimizing pressure drop. Key Features Transitions between 6-inch and 5-inch round duct diameters in a single fitting Suitable for both reducing and increasing duct diameter depending on airflow direction Designed for integration into standard round duct supply and return systems Compact form factor reduces the need for additional transition fittings Compatibility Designed as an OEM-style replacement and new-install fitting for residential and light commercial round…