Parker 3/8 X 1/4 Ff-s Hex Plug 6000 Psi Mnptf

Product Description

The PARKER 3/8 X 1/4 FF-S is a straight hex plug fitting designed to seal male pipe threads in high-pressure hydraulic and industrial fluid systems. It uses a MNPTF (Male National Pipe Taper Fuel) thread form, which provides a pressure-tight mechanical seal without requiring additional sealant tape in many applications. Rated to 6,000 psi maximum working pressure, this fitting is built for demanding service environments where reliable thread sealing is critical. The hex head allows installation and removal with standard wrenches. Licensed plumbers, pipefitters, and hydraulic system technicians are the typical installers.

This hex plug is suited for use in industrial hydraulic circuits, pneumatic systems, fuel lines, and high-pressure fluid distribution manifolds where a threaded port must be closed off. The straight fitting shape makes it a direct port plug. With a 3/8 inch to 1/4 inch male thread configuration, it is commonly used to reduce or cap off ports on valves, cylinders, pumps, and manifold blocks in both stationary and mobile equipment applications.

Key Features

• 6,000 psi maximum working pressure rating for high-pressure hydraulic and industrial service
• MNPTF thread form provides a pressure-tight seal on tapered female port threads
• Straight hex plug shape for direct port closure without bends or offsets
• 3/4 inch hex size for use with standard open-end or combination wrenches
• Overall length of 1-7/16 inches for compact installation in tight spaces
• Lightweight at 0.1 pounds, minimizing added system weight

Compatibility

Designed as an OEM-style replacement or service fitting for high-pressure hydraulic and industrial fluid systems requiring a straight MNPTF hex plug to seal a threaded port.

Installation Notes

Installation should be performed by a qualified pipefitter, hydraulic technician, or licensed plumber following applicable codes such as the IPC or relevant industrial safety standards. Depressurize and isolate the system completely before removing or installing any fittings. Apply thread sealant or PTFE tape as appropriate for the fluid service and verify that the female port thread form is compatible with MNPTF before installation. Do not overtighten — use a calibrated torque wrench and follow the fitting manufacturer's published torque specifications for the thread size.