#6 x 3/4-16 (#8) Radius O-Ring Fitting Black

The #6 x 3/4-16 (#8) Radius O-Ring Fitting Black by FRAGOLA is a precision hydraulic and fuel system adapter designed to connect AN male ports of different sizes in high-pressure applications. This straight-configuration fitting bridges 6 AN male threads to 8 AN male threads, making it essential for custom fuel systems, hydraulic lines, and performance vehicle builds where port size conversion is required. Fabricated from lightweight aluminum and finished in black anodize, this adapter combines durability with corrosion resistance for long-term reliability in demanding environments.

The radius O-ring design provides superior sealing performance compared to traditional JIC flare fittings, eliminating the risk of leaks under pressure cycles and vibration. The straight-port geometry allows fluid to flow without turbulence, reducing pressure drop across the connection and improving overall system efficiency. Black anodized aluminum construction resists oxidation and abrasion while keeping component weight minimal—critical for race cars, hot rods, and weight-sensitive applications. The O-ring face seal (ORFS) connection method seats the ring against a machined face rather than relying on thread compression, delivering consistent, repeatable performance across thousands of pressure cycles.

This fitting is ideal for builders connecting fuel rails, intercooler lines, transmission coolers, and custom hydraulic circuits where mixed AN port sizes are unavoidable. Installation requires only a wrench—no special flaring tools needed—making field repairs and system modifications straightforward. Verify that both the 6 AN male and 8 AN male ports on your system are compatible with O-ring face seal connections before purchase. FRAGOLA fittings are trusted by professional fabricators and performance shops for their leak-free seals and repeatable quality across thousands of installations.