20AN Male to 16AN O-ring Port Adapter Black

The 20AN Male to 16AN O-ring Port Adapter Black from REDHORSE PERFORMANCE is an essential hydraulic fitting for custom fuel system builds, turbo setups, and high-flow cooling loops where port size reduction is required. This adapter bridges the gap between larger 20AN supply lines and smaller 16AN component ports, allowing you to step down line sizes without compromising reliability or introducing leak points. Whether you're fabricating a custom fuel rail, connecting auxiliary coolers, or integrating a secondary fuel pump, this stepped adapter simplifies plumbing complexity and eliminates the need for costly custom hose configurations.

Engineered with REDHORSE's signature O-ring seal technology, the 20AN Male to 16AN O-ring Port Adapter uses a precision-machined body and integrated O-ring groove to create a leak-free connection that handles sustained pressure without weeping or seepage. The male 20AN inlet threads directly into female 20AN ports, while the 16AN O-ring port outlet accepts standard 16AN fittings—eliminating thread-seal tape and Teflon concerns that plague older JIC designs. Machined from aluminum alloy and finished in protective black anodize, this adapter resists corrosion from fuel exposure, coolant chemistry, and salt-air environments while maintaining a clean aesthetic in engine bays.

Mechanics and fabricators building street machines, track cars, and forced-induction platforms rely on REDHORSE stepped adapters to downsize fuel delivery circuits, transmission cooler lines, and intercooler loops without sacrificing flow capacity. The compact 5.75-inch body fits tight engine compartments, and the O-ring design eliminates the risk of system contamination from thread tape debris—critical when protecting fuel injectors and precision fuel pumps. Install one inline where a 20AN feed line connects to a 16AN component, torque the male end to spec, and hand-tighten the 16AN fitting until snug; no special tools or sealant required for years of vibration-resistant service.