6AN Female Swivel To 1/8NPT Male Adapter STR

The 6AN Female Swivel to 1/8NPT Male Adapter STR from REDHORSE PERFORMANCE is an essential fitting for custom fuel system builds, turbo plumbing, and precision fluid transfer applications where port sizing differs across components. This straight adapter bridges the gap between AN (Army-Navy) hose standards and NPT (National Pipe Thread) ports, making it invaluable for builders integrating aftermarket fuel rails, regulators, gauges, and engine management hardware that use mixed port standards. Whether you're upgrading a carbureted engine's fuel delivery or connecting a forced-induction system, this adapter eliminates the need for expensive custom machining or settling for suboptimal port conversions.

The 6AN female swivel design allows hose connection via a -6 hose end (industry-standard 3/8" outer diameter hose), while the 1/8" NPT male port threads directly into engine blocks, fuel blocks, or manifolds without additional adapters. The swivel feature compensates for minor misalignment during installation, reducing vibration-induced wear and preventing hose chafing—critical for reliability under sustained boost or high fuel pressure. REDHORSE PERFORMANCE fittings are manufactured to strict SAE J518 standards with precision-machined bodies and smooth internal passages that minimize turbulence and pressure drop, essential for maintaining fuel system efficiency and consistency across throttle transitions and load conditions.

This adapter fits racing engines, street performance builds, and OEM conversion projects where factory fuel systems are replaced with aftermarket components. It pairs seamlessly with fuel pressure regulators, remote fuel blocks, turbocharger feed lines, and gauge sender ports on engine blocks or cylinder heads that feature 1/8" NPT inlets. Installation is straightforward: thread the NPT male end into the engine port using thread sealant (PTFE tape or anaerobic compound recommended), then attach your braided AN hose via the female swivel coupling. The lightweight design (0.065 lbs) and compact form factor make it ideal for tight engine bay configurations where clearance limits hose routing options.