Uponor LF4577575 3/4 in Pex X Fnpt Brass Female Adapter

Product Description

The UPONOR LF4577575 is a lead-free brass female adapter designed to transition a 3/4-inch PEX tubing run to a 3/4-inch female NPT threaded connection. This fitting is used in potable water systems where a PEX line must connect to a threaded valve, manifold port, fixture, or other NPT-threaded component. The lead-free brass construction meets current federal and state requirements for fittings used in drinking water applications. Installation is handled by licensed plumbers working on residential or light commercial hydronic or domestic water piping systems.

This adapter is suited for new construction and retrofit plumbing projects where PEX tubing is being connected to existing or new threaded pipe components. It is appropriate for use in hot and cold domestic water distribution systems. The PEX end accepts a standard expansion or crimp connection depending on the installation method in use, while the FNPT end threads directly onto a compatible male-threaded fitting or port.

Key Features

• Lead-free brass construction meets safe drinking water act requirements for potable water use
• 3/4-inch PEX-to-FNPT transition allows direct connection between flexible PEX tubing and threaded components
• Domestic manufacturing designation supports project compliance requirements
• Compatible with standard PEX installation tooling for crimp or expansion-style connections

Compatibility

Designed as an OEM-style replacement and standard-use fitting for 3/4-inch PEX plumbing systems requiring a female NPT threaded outlet.

Installation Notes

Installation should be performed by a licensed plumber in accordance with local plumbing codes and IPC guidelines. Shut off the water supply and relieve system pressure before making any connections. Use appropriate PEX crimp or expansion tooling on the PEX end, and apply thread sealant tape or compound to the male NPT threads being engaged on the FNPT side. Do not over-tighten the threaded connection, as brass fittings can crack under excessive torque.

Technical Specifications

• Connection Type: PEX x FNPT
• Size: 3/4 inches
• Material: Brass
• Lead-Free: Yes
• Origin: Domestic

Standard Information

• Brand: UPONOR
• Manufacturer Part Number: LF4577575