This duct increaser is designed to fit with our economy fan duct connector assemblies. It will work with 5" round duct systems, is UL 94 compliant for flammability, and made in the USA.
- Expand from 4" to 5" duct
- Allows easy connection of a ventilation fan (with 4" round duct connector) to 5" round ducting
- UL 94 compliant for flammability