An A/N (Army/Navy) fitting is a type of fitting used in aviation, automotive, and hydraulic systems. These fittings are part of a standardized system that allows for easy assembly and disassembly of fuel, oil, and hydraulic systems. The "A/N" specification refers to the standard set by the military for these fittings, but they've become widely used in a variety of industries.

A/N fitting sizes

• The number (e.g., -6, -8) refers to the size of the fitting, specifically the outer diameter of the tube or hose in sixteenths of an inch.

For example:

• -6 means a 6/16" or 3/8" outer diameter.
• -8 means an 8/16" or 1/2" outer diameter.

Basic Specs for A/N Fittings:

For -6 (3/8" outer diameter):

• Thread size: 3/4"-16
• Inside diameter (ID) of the hose or tube: Around 0.375 inches (3/8")
• Outer diameter (OD): 0.5625 inches (9/16")
• Dash size: -6
• Flow capacity: Suitable for moderate flow, often used for brake lines, fuel lines, and hydraulic systems.

For -8 (1/2" outer diameter):

• Thread size: 7/8"-14
• Inside diameter (ID) of the hose or tube: Around 0.500 inches (1/2")
• Outer diameter (OD): 0.750 inches (3/4")
• Dash size: -8
• Flow capacity: Suitable for larger flow, often used in applications like fuel, oil, or coolant lines.

Other Considerations:

• Material: A/N fittings can be made of materials like aluminum, steel, or stainless steel depending on the application.
• Seal Type: Most A/N fittings use a cone-shaped or flare sealing surface to ensure a leak-free connection. These are typically paired with braided stainless-steel hoses or rigid tubes.