4AN Flare Plug 2/pkg Blue

The 4AN Flare Plug 2/pkg Blue from Redhorse Performance is an essential hydraulic and fuel line termination component designed for custom fuel systems, power steering setups, and high-performance cooling circuits. These plugs seal off unused 4AN ports in your fuel rail, carburetor feed lines, or transmission cooler circuits, preventing fluid leakage and contamination while maintaining system integrity under pressure. Built for mechanics and fabricators who demand reliability, this two-pack ensures you have backup plugs on hand during installation or when reconfiguring your vehicle's fluid delivery architecture.

Redhorse Performance's 4AN Flare Plug features a precision-engineered flare nut design that seats firmly into standard 4AN ports without additional adapters or fittings. The blue anodized aluminum construction provides both corrosion resistance and visual identification, making it easy to distinguish from other line sizes during engine bay work or system troubleshooting. The flare seat geometry ensures a leak-free compression fit across full operating pressure ranges, whether you're running a carbureted setup, EFI fuel system, or custom coolant circuit—critical when working with pressurized systems where even minor weeping can cause fluid loss and performance issues.

Engine builders, fuel system fabricators, and performance enthusiasts routinely use 4AN Flare Plugs when converting carburetor fuel rails to EFI injection, upgrading to larger fuel pumps, or installing aftermarket cooling lines. These plugs work with any 4AN port configuration—Speedway Motors fuel rails, Holley carburetors with fuel inlet ports, custom-bent -4 braided steel lines, and most aftermarket fuel pressure regulators. The two-pack format accommodates typical single-engine projects or provides spares for future builds. Installation requires only a standard wrench; hand-tighten the flare nut to seat, then snug with a flare-nut wrench to lock the seal without over-torquing and cracking the aluminum body.