#3 An Aluminum Tube Nut

The #3 AN aluminum tube nut is a precision hydraulic and pneumatic fitting component designed for fluid power systems requiring reliable, leak-free connections. This set of six blue anodized aluminum tube nuts is essential for technicians, engineers, and equipment operators who depend on secure tubing assemblies in industrial machinery, aircraft systems, mobile equipment, and custom hydraulic installations. The 3 AN designation (equivalent to 3/16-inch tube outer diameter) represents a standard aerospace and industrial specification recognized across North America.

Manufactured by AEROQUIP, a globally trusted name in fluid power connectors, the #3 AN aluminum tube nut features a durable blue anodized aluminum construction that resists corrosion while remaining lightweight for weight-sensitive applications. The anodized finish provides enhanced durability and visual identification in color-coded system layouts. The nut threads onto male JIC fittings with a standard pitch and secures tubing without requiring sealant tape or additional thread compounds, creating a metal-to-metal seal when properly torqued. The compact design—measuring 2.35 x 1.1 x 3.75 inches and weighing just 0.05 lbs per unit—ensures easy handling and installation in confined spaces typical of engine bays, flight decks, and industrial control systems.

Professionals working with 3/16-inch OD tubing benefit most from purchasing this six-piece set, as replacement and repair work often requires multiple fittings to reduce downtime and inventory costs. The #3 AN tube nut is fully compatible with standard 3/16-inch seamless steel, stainless steel, or nylon tubing used in automotive fuel systems, aircraft fuel and hydraulic lines, industrial pressure systems, and custom racing applications. Installation is straightforward: hand-start the nut onto a male AN fitting, then use a wrench to torque to manufacturer specifications—typically 18–22 foot-pounds depending on system pressure. Stock this proven AEROQUIP component for emergency repairs, OEM replacements, or system upgrades.