#4 An Flare To 3/8in Pipe

The AEROQUIP #4 AN Flare to 3/8 Inch Pipe adapter is a straight-port AN male to NPT male fitting engineered for hydraulic and pneumatic systems where reliable threadless and threaded port transitions are critical. This adapter allows seamless connection between AN (Army-Navy) flare fittings and standard NPT pipe threads, making it essential for custom hydraulic lines, fuel systems, and high-pressure fluid transfer applications across industrial, marine, and mobile equipment platforms.

Constructed from steel and finished with zinc plating, this AN to NPT adapter provides corrosion resistance suitable for both indoor and moderately corrosive environments. The #4 AN flare size (standard 1/4-inch tubing) paired with 3/8-inch NPT male threading delivers predictable flow characteristics and thread strength for systems operating at typical industrial pressures. The straight design eliminates elbow configurations, reducing fitting count and potential leak points in tight installations. Zinc plating extends service life while maintaining the adapter's ability to seal reliably under vibration and thermal cycling.

This fitting is commonly used in hydraulic brake systems, power steering assemblies, fuel distribution networks, and pneumatic control circuits where AN flare connections must interface with NPT-threaded ports on manifolds, regulators, or machine components. Technicians and engineers select AN-to-NPT adapters when retrofitting systems, connecting aftermarket components to OEM ports, or consolidating mixed-thread installations into a single coherent hydraulic architecture.

AEROQUIP maintains a strong market position as a supplier of hydraulic connectors and adapters; this specific adapter is compact (2.4 × 1.05 × 3.75 inches) and lightweight (0.1 lbs), fitting easily into space-constrained engine bays and equipment enclosures. Whether you're building a custom fluid system or replacing a worn transition fitting, this steel AN-to-NPT adapter delivers the port flexibility and corrosion protection required for long-term service reliability.