Adapter Straight #8 Flare 1/4in NPT

The Adapter Straight #8 Flare 1/4in NPT is a critical hydraulic and pneumatic fitting for marine fuel systems, engine cooling loops, and high-pressure applications on boats and watercraft. This male-to-male adapter bridges an 8 AN (Army-Navy) flare connection to a 1/4-inch NPT (National Pipe Thread) port, making it essential when upgrading fuel delivery systems, replacing worn fittings, or retrofitting non-standard engine compartment layouts. Any serious boater working with mechanical systems or performance fuel systems will recognize this fitting as a workhorse for eliminating leaks and ensuring secure, code-compliant connections.

Machined from aluminum and finished in durable blue anodize, the Adapter Straight #8 Flare 1/4in NPT resists corrosion in salt-spray and freshwater environments while maintaining structural integrity under vibration and pressure cycling. The straight design—without elbows or bends—minimizes turbulence in fuel or coolant flow and reduces stress concentration at the fitting joint. The 8 AN flare end employs a 37-degree cone seat that matches industry-standard hose fittings, while the NPT male thread on the opposite end taps directly into female NPT ports commonly found on fuel filters, carburetors, water manifolds, and engine blocks.

This adapter is ideal for boaters restoring vintage engines, upgrading fuel systems to meet modern standards, or integrating aftermarket fuel injection and cooling upgrades. It is compatible with any hose assembly rated for 8 AN flare fittings and any engine or component with a 1/4-inch NPT female port. Installation requires a wrench on both the flare nut and the body; thread-seal tape or pipe dope on the NPT thread prevents leaks. Weighing just 0.05 lbs and compact in profile, it fits tight engine bays and galley spaces without obstruction.