Uponor LF4521313 Male Adapter 1-1/4 in Pex X Mnpt Brass

Product Description

The UPONOR LF4521313 is a lead-free brass male adapter designed to transition from 1-1/4 inch PEX tubing to a 1-1/4 inch male NPT threaded connection. Constructed from domestic lead-free brass, this fitting meets low-lead compliance requirements for potable water systems. The PEX side accepts an expansion-style or crimp connection depending on the system specification, while the MNPT end threads directly into a female-threaded port on valves, manifolds, or equipment. Plumbers and pipefitters install this adapter wherever a PEX distribution line must terminate at a threaded fitting, making it a standard transition component in residential and light commercial plumbing rough-in work.

This adapter is suited for potable water supply systems, hydronic heating distribution, and radiant floor applications where PEX tubing connects to threaded iron or brass components. Typical install scenarios include connecting PEX mains to shutoff valves, water heaters, manifold headers, and equipment inlets. The domestic-sourced brass construction supports compliance with Buy American provisions on applicable projects.

Key Features

• Lead-free brass construction meets low-lead requirements for potable water contact
• 1-1/4 inch PEX connection transitions to 1-1/4 inch male NPT thread
• Domestic material sourcing supports Buy American compliance documentation
• Compact adapter profile simplifies tight rough-in connections
• Compatible with standard PEX expansion and crimp installation methods

Compatibility

Designed as an OEM-style transition fitting for 1-1/4 inch PEX tubing systems requiring a male NPT threaded outlet, typical in residential and light commercial potable water and hydronic piping installations.

Installation Notes

Installation should be performed by a licensed plumber in accordance with applicable local plumbing codes and IPC guidelines. Shut off the water supply and relieve system pressure before making any connections. Apply thread sealant tape or pipe dope to the MNPT threads before engaging the fitting; do not overtighten threaded connections into soft-seated ports. The PEX end should be prepared and connected using the appropriate expansion ring or crimp ring method per the tool and tubing manufacturer specifications.

Technical Specifications

• Connection Type: PEX x MNPT
• Size: 1-1/4 inches
• Material: Lead-Free Brass
• Origin: Domestic

Standard Information

• Brand: UPONOR
• Manufacturer Part Number: LF4521313