4 Way Square Bulkhead #8 and #10 O-Ring

The 4 Way Square Bulkhead #8 and #10 O-Ring is a critical hydraulic and pneumatic component designed for high-performance engine cooling systems, transmission coolers, and custom fuel delivery setups. Built for serious automotive enthusiasts and fabricators who demand precision-engineered plumbing solutions, this bulkhead fitting serves as the backbone of leak-free fluid transfer in modified vehicles. Whether you're upgrading a vintage hot rod's air conditioning system, installing aftermarket oil coolers, or fabricating bespoke fuel systems, this dual-size bulkhead accommodates both #8 and #10 AN (Army-Navy) hose standards in a single compact fixture.

The square bulkhead design provides four connection ports, allowing multi-directional fluid routing without requiring additional adapters or manifold blocks—a significant advantage when space is limited in engine bays or custom chassis builds. The integrated O-ring seal eliminates reliance on external sealing tape or sealant, reducing installation time and minimizing risk of micro-leaks that plague unreliable setups. The machined aluminum or brass construction withstands sustained pressure cycles while maintaining dimensional stability across temperature swings common in performance applications. This fitting is compatible with standard AN braided hose, push-to-connect pneumatic tubing, and metric equivalents, making it exceptionally versatile across restoration and modern modification projects.

Mechanics and fabricators restoring classic air conditioning systems, building custom cooling loops, or integrating auxiliary fuel systems will appreciate the time savings and confidence this component delivers. Install by threading the bulkhead into a prepared square boss or manifold cavity, then connect your #8 and #10 hoses to the port configuration that suits your circuit design. Ensure proper torque sequencing to prevent O-ring extrusion while maintaining system integrity under boost or sustained highway loads. This is an ideal choice for anyone serious about eliminating leaks, simplifying plumbing architecture, and achieving the professional-grade reliability expected in high-dollar builds.