#4 To 3/8-24 Inverted Steel Adapter

The AEROQUIP #4 to 3/8-24 Inverted Steel Adapter is a precision hydraulic fitting designed to connect AN (Army-Navy) sized hardline tubing to inverted flare threaded ports commonly found in industrial, aerospace, and mobile equipment applications. This straight adapter bridges two industry-standard port configurations, enabling reliable fluid transfer across systems that use different connection standards.

The adapter features a 4 AN male connection on one end and a 3/8-24 inverted flare male thread on the other, compatible with 3/16-inch hardline tubing. Constructed from steel with zinc oxide coating, the fitting resists corrosion in varied operating environments—critical for systems exposed to moisture, temperature fluctuations, or outdoor storage. The inverted flare design ensures a positive, leak-resistant seal under pressure, a fundamental requirement in hydraulic systems where fluid containment is non-negotiable. The straight configuration eliminates directional complications during installation and maintenance.

Technicians and operators in mobile hydraulics, agricultural equipment, construction machinery, and aerospace maintenance rely on AEROQUIP adapters to maintain system integrity when retrofitting lines or integrating components across different equipment generations. The compact form factor and straightforward design simplify troubleshooting and component replacement in tight installation spaces where access is limited.

This adapter is part of the broader AN standardized fitting ecosystem, widely adopted across military, commercial, and industrial hydraulic networks. Stocking verified AEROQUIP components ensures system reliability and reduces downtime from incompatible or corroded connections.