Parker 3/8 Ff-s Hex Plug 3/8 Inch Mnptf 6000 Psi

Product Description

The PARKER 3/8 FF-S is a straight hex plug designed to seal open pipe ports in high-pressure hydraulic and pneumatic systems. It features a 3/8 inch male MNPTF (Dryseal) thread that forms a pressure-tight seal without a separate sealant, though thread sealant tape is commonly applied in field installations. Rated to 6,000 psi maximum working pressure, this plug is built for demanding industrial service. The hex drive design allows installation with standard wrenches. Weighing 0.2 pounds, it is a compact, single-piece fitting suited for inline port sealing tasks across a wide range of fluid power and instrumentation applications.

This hex plug is used to cap or block unused ports on valves, manifolds, cylinders, pumps, and other hydraulic or pneumatic components. It is appropriate for both industrial plant maintenance and mobile equipment applications where a reliable, leak-free port closure is required. The MNPTF thread classification makes it well suited for high-pressure instrumentation lines and fluid transfer systems where pressure integrity is critical. Licensed pipefitters, hydraulic system technicians, and industrial maintenance mechanics are the primary installers.

Key Features

• 6,000 psi maximum working pressure rating for high-pressure hydraulic and pneumatic service
• 3/8 inch MNPTF (Dryseal National Pipe Taper Fuel) male thread for pressure-tight connections
• Straight hex plug configuration for straightforward port sealing
• 3/4 inch hex size for use with standard open-end or box wrenches
• Overall length of 1-7/16 inches for compact fitment in tight port locations
• Lightweight at 0.2 pounds for easy single-hand installation

Compatibility

Designed as an OEM-style replacement or maintenance fitting for hydraulic and pneumatic systems with 3/8 inch MNPTF ported connections rated to 6,000 psi or below.

Installation Notes

Installation should be performed by a qualified hydraulic technician or pipefitter. Depressurize and isolate the system completely before removing or installing any fittings. Apply thread sealant tape or an appropriate anaerobic thread sealant to the male threads before installation; do not overtighten, as MNPTF threads are tapered and can crack ports if over-torqued. Verify system pressure rating does not exceed the 6,000 psi maximum working pressure of this fitting before returning the system to service.