#4 Union Fitting

The FRAGOLA #4 Union Fitting is a precision aluminum adapter designed for high-performance fuel system applications, ensuring reliable and leak-free connections. This fitting is essential for those building turbocharged engines, upgrading fuel delivery systems, or restoring classic vehicles with modern fuel injection. Its robust construction meets the demands of mechanics and automotive enthusiasts alike.

Crafted from lightweight aluminum alloy, the #4 union fitting is engineered to handle elevated fuel pressures without compromise. The union design allows for a secure connection between two fuel lines, utilizing a center ferrule and threaded body to distribute clamping force evenly. This design minimizes the risk of hose separation under vibration or pressure spikes, making it a reliable choice for high-performance applications.

Ideal for custom fuel systems, turbo builds, and supercharged platforms, this fitting is compatible with standard #4 SAE hose (1/4-inch nominal). Its compact profile of 1.35 x 1.05 x 4 inches fits snugly in tight engine compartments, making it a practical choice for performance upgrades. Mechanics and enthusiasts can trust FRAGOLA fittings to meet their horsepower goals without the uncertainty of inferior adapters.