Twist-Lok Hose End #4 Str Black

The Twist-Lok Hose End #4 Str Black from Russell is a precision-engineered fitting designed for high-performance fuel and coolant line systems in modified vehicles and racing applications. Whether you're building a custom fuel injection setup, upgrading cooling capacity, or assembling a competition engine bay, this 4 AN straight hose end provides the secure, leak-free connection that separates a reliable build from a roadside failure. Mechanics and fabricators choose Twist-Lok fittings for their proven track record in demanding environments where vibration, pressure cycling, and thermal stress constantly challenge inferior hardware.

This fitting features a 4 AN female port that accepts 4 AN hose with a barbed end, secured by Russell's signature twist-lock mechanism—a reusable, tool-free design that eliminates hose slippage without requiring clamps or specialized crimpers. The black anodized aluminum construction balances weight savings with corrosion resistance, critical for underhood longevity in salt-air or high-moisture environments. The straight orientation makes it ideal for tight engine bays where angled fittings cannot fit; paired with matching hose and complementary AN fittings, it forms the backbone of professional-grade fuel and coolant delivery systems that withstand sustained boost pressure, cryogenic coolant additives, and continuous high-RPM operation.

This hose end is essential for engine builders, suspension upgraders, and fuel system fabricators working on street performance cars, turbo conversions, and road-racing platforms where stock rubber fuel lines and factory coolant passages are insufficient. Its compact 2.7 x 1.9 x 5.75 inch footprint and lightweight 0.05 lb profile minimize space intrusion and fastener load, making it compatible with high-volume fuel and coolant hose assemblies (0.5 inch inner diameter, standard AN-4 bore). Installation is straightforward: insert the hose's barbed end into the female port and twist the knurled collar clockwise until hand-tight—no crimper, no clamp, no guesswork. Pair it with Russell or equivalent 4 AN male fittings, adapters, and braided stainless hose for complete system integrity.