Port Plug O-Ring Seal 12an (1pk)

The Port Plug O-Ring Seal 12AN from EARLS is a precision hydraulic fitting designed to cap and seal open 12 AN ports in fluid systems, preventing contamination and leakage during assembly, maintenance, or system downtime. Whether you're building a custom cooling circuit, fuel system, or brake line assembly, this port plug ensures critical connection points remain protected and ready for service. Engineered for professionals and enthusiasts who demand reliability in high-pressure applications, this single-unit seal is essential for any serious mechanical build or repair.

Constructed from aluminum and finished in black anodize, the Port Plug O-Ring Seal 12AN features a hex head design for secure wrench engagement and an integrated O-ring that creates a positive, reusable seal without thread-dependent compression. The black anodized finish provides corrosion resistance and durability in high-temperature and fluid-exposure environments. The 12 AN fitting size (3/4-16 thread standard) ensures compatibility with industry-standard 12 AN hose adapters and manifold ports, while the O-ring construction allows the plug to be removed and reinstalled repeatedly without degrading seal integrity—critical for systems requiring frequent service access.

This port plug is ideal for anyone working with custom or OEM hydraulic, fuel, transmission, or cooling systems where port protection is non-negotiable. Install on any open 12 AN port to maintain system cleanliness during assembly, shipping, or storage; simply remove and replace when reconnecting hose or hard-line fittings. Compatible with any manifold, cooler, or engine block featuring standard 12 AN female ports, the EARLS AT981412ERL delivers professional-grade sealing in a compact, lightweight package that belongs in every technician's toolkit.