Parker 5 P5ON-S Hex Plug 1/2-20 Unf 6000 Psi O-ring

Product Description

The PARKER 5 P5ON-S is a male straight thread O-ring hex plug designed to seal hydraulic and fluid system ports in industrial and mobile equipment applications. Threaded to a 1/2-20 UN/UNF-2A standard, it provides a leak-resistant closure rated to 6,000 psi maximum working pressure. The hex drive design allows installation with standard wrench tooling. The straight thread O-ring connection style seats against a machined boss surface, creating a reliable metal-to-face seal that resists vibration loosening better than tapered pipe thread designs. This fitting is typically installed by hydraulic technicians, millwrights, and fluid power specialists maintaining or building hydraulic circuits, manifolds, and power units.

This plug is suited for use in high-pressure hydraulic systems where a port needs to be blanked off or temporarily capped. Common applications include closing unused ports on hydraulic cylinders, valves, manifolds, and pump housings. The straight thread O-ring configuration conforms to SAE standard 090109A, making it appropriate for systems built to SAE hydraulic fitting specifications. It is a compact, single-piece plug well suited to tight-clearance installations where bulk is a concern.

Key Features

• 6,000 psi maximum working pressure rating for demanding hydraulic service
• 1/2-20 UN/UNF-2A male straight thread with O-ring sealing for leak-resistant port closure
• 5/8-inch hex drive for standard wrench installation
• 11/16-inch overall length for compact fitment in tight-clearance ports
• Conforms to SAE 090109A standard
• Lightweight at 0.03 pounds — minimal system weight impact

Compatibility

Designed as an OEM-style straight thread O-ring port plug for hydraulic systems built to SAE 090109A specifications with 1/2-20 UN/UNF female straight thread boss ports rated at or above 6,000 psi.

Installation Notes

Installation should be performed by a qualified hydraulic technician or fluid power specialist. Depressurize and bleed down the hydraulic circuit fully before removing or installing any fittings or plugs. Inspect the O-ring for damage before installation and lubricate it lightly with system-compatible fluid. Do not overtighten — straight thread O-ring fittings seal on the O-ring face, not on thread torque, and overtightening can damage the O-ring or boss seat.