SKU: ALL 50133
UPC: 848238026191
MPN: ALL50133
The Inverted Flare Union 4-Pack 3/8-inch Line 5/8-18 from Allstar Performance is a precision brass fitting adapter designed for high-pressure hydraulic and fuel line systems. This four-piece set provides reliable dual female inverted flare connections in the 5/8-18 thread specification, meeting the exacting standards required in motorsports, performance automotive, and industrial applications where leak-free operation is non-negotiable.
Each union fitting is machined from brass and features natural finish, delivering excellent corrosion resistance and compatibility with both fuel and hydraulic fluids. The inverted flare design creates a metal-to-metal seal that distributes pressure evenly across the connection point, reducing the risk of leakage under vibration and thermal cycling—critical in engine bays and fuel systems subject to extreme conditions. The 3/8-inch line size pairs with standard 5/8-18 thread specifications, ensuring compatibility with most race fuel systems, brake line assemblies, and custom hydraulic installations.
This four-pack is ideal for fabricators, engine builders, and performance technicians assembling or repairing fuel delivery systems, brake circuits, and power steering lines. Allstar Performance fittings are engineered to withstand high-vibration environments and rapid pressure cycling, making them essential components in drag racing, road racing, off-road, and street performance builds. A redundant set ensures spares are available for mid-season repairs or system modifications without sourcing delays.
Category: Fitting - Adapter - Straight Dual 5/8-18 Inverted Flare Female. Allstar Performance is recognized in the motorsports and performance automotive industry for precision-manufactured hydraulic and fuel system components built to withstand extreme duty cycles. These unions are stocked by professional shops and serious builders seeking durable, repeatable connections without fail points.
Weight: 0.28 lbs per pack. Dimensions: 4 × 0.9 × 7.05 inches. SKU ALL 50133 | UPC 848238026191.
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