#3 Caps

EARLS #3 Aluminum Caps are precision-engineered fittings designed for AN (Army-Navy) standard fluid line systems. These blue anodized caps serve as reliable end-of-line terminators for 3 AN hydraulic or fuel lines, commonly found in high-performance automotive, aviation, and racing applications where system integrity and corrosion resistance are critical.

The aluminum construction with blue anodized finish provides dual benefits: reduced weight compared to steel alternatives and enhanced corrosion protection in demanding environments. The 3 AN thread size is the industry standard for medium-flow applications, compatible with all standard AN fittings and hoses meeting MIL-A-25042 specifications. Supplied as a pair, these caps ensure you have complete coverage for both ends of a closed circuit or can outfit dual systems. The compact dimensions (1.15 x 0.5 x 2.4 inches) make them suitable for tight installation spaces typical in engine bays and equipment panels.

These fittings are essential for technicians and enthusiasts maintaining or building custom fluid systems—from street rods and racing engines to experimental aircraft and marine applications. Whether protecting open AN lines during storage, sealing test circuits, or finalizing a system build, EARLS caps provide a proven, manufacturer-backed solution. The anodized finish resists oxidation better than bare aluminum, extending service life in corrosive salt-air or moisture-heavy environments.

AN-standard fittings represent the foundation of professional fluid-system design. Unlike proprietary adapters, 3 AN components are fully interchangeable across manufacturers and industries—a critical advantage when sourcing replacement or upgrade parts. EARLS has maintained consistent quality in the aftermarket performance sector, making these caps a straightforward addition to any AN-equipped build or restoration.