Parker 4-4-4 Stx-s Steel Male Branch Tee 1/4 in Flare

Product Description

The PARKER 4-4-4 STX-S is a steel flared tube male branch tee fitting designed for high-pressure hydraulic and fluid power plumbing applications. It features a 37-degree flare connection with male NPTF (National Pipe Taper Fuel) thread ends, providing a leak-resistant seal under demanding dynamic conditions. Rated to 6000 psi maximum working pressure and suitable for service temperatures up to 500 degrees F, this fitting is built for environments where reliability under pressure is non-negotiable. The all-steel construction makes it appropriate for use in fuel, air, oil, and hydraulic lines where softer materials would be inadequate. Licensed plumbers, pipefitters, and hydraulic system technicians are the primary installers of this type of fitting.

This fitting is used in residential, commercial, and industrial fluid power systems wherever a branch connection is needed in a 37-degree flare tube line. The male branch tee configuration allows a single inline tube run to be teed off to a third port using MNPTF thread engagement. Typical install scenarios include hydraulic control panels, fuel delivery systems, and compressed air distribution lines. The 1/4 inch tube OD and 1/4 inch thread size make it well suited for smaller-bore tubing circuits common in instrumentation and light hydraulic applications.

Key Features

• 37-degree flare angle per SAE J514 and ISO 8434-2 standards for secure, leak-resistant tube connections
• Maximum working pressure of 6000 psi for high-pressure hydraulic and fuel system use
• Rated to 500 degrees F (260 degrees C) maximum working temperature
• All-steel construction for durability in fuel, oil, air, and hydraulic service
• NPTF thread standard provides a pressure-tight mechanical seal without sealant tape dependency
• Flare x MNPTF end connections allow direct inline branch tee configurations in tubing circuits

Compatibility

Designed as an OEM-style replacement or new-installation fitting for 37-degree flare tube systems using 1/4 inch OD tubing and 1/4 inch NPTF male thread ports, conforming to SAE J514, SAE 070425, and ISO 8434-2 specifications.

Installation Notes

Installation should be performed by a qualified pipefitter, plumber, or hydraulic technician familiar with flared tube fittings and NPTF thread engagement. De-energize and depressurize the system fully before disconnecting or installing any fitting. Inspect the flare seat and tube end for damage or burrs before assembly, as surface defects compromise the seal. Consult applicable codes such as the IPC or IFGC depending on the fluid service, and follow SAE J514 assembly guidelines for proper flare engagement.