EFI Fitting #6 Push-On to 5/16 Male Hard Tube

The EFI Fitting #6 Push-On to 5/16 Male Hard Tube is a precision adapter designed for high-performance fuel and fluid systems where reliable connections are non-negotiable. Built for automotive enthusiasts, mechanics, and performance shops, this straight-path fitting eliminates the weak points that can lead to leaks or system failures in fuel injection systems, hydraulic lines, and pressurized applications. The push-on inlet accommodates hard tube fittings with exact geometric tolerances, while the 5/16 SAE male outlet provides a universal quick-disconnect connection point that's recognized across industrial and motorsport standards.

Manufactured by RUSSELL—a trusted name in fluid systems engineering—this fitting features a zinc-plated steel construction that resists corrosion while maintaining structural integrity under sustained pressure and temperature cycling. The #6 AN (Army-Navy) to 5/16 SAE conversion geometry ensures compatibility with legacy and modern fuel systems, offering a direct solution for adapting hard tube assemblies to quick-disconnect coupling standards. Zinc plating provides durable protection in underhood environments, preventing rust and oxidation that could compromise thread sealing or fitting integrity over years of service.

This adapter excels in custom fuel system builds, engine swaps, and performance modifications where standard OEM fittings don't match aftermarket fuel rails or quick-disconnect systems. Professionals installing fuel injection upgrades, turbo conversions, or remote fuel cell configurations will appreciate the straight configuration, which minimizes turbulence and pressure loss compared to angled fittings. Installation is straightforward: ensure the hard tube is properly cut and deburred before pushing onto the #6 AN inlet, then secure the 5/16 SAE male end into your quick-disconnect coupling or fuel line adapter. Compact dimensions and lightweight design make it ideal for space-constrained engine bays.