AN Male-to-Male Unions & Reducer/Expander Adapters

Connect two female AN hose ends or step between AN sizes with precision-machined male-to-male adapters. Perfect for extending lines, bridging components, or cleanly adapting size without a stack of fittings.

What’s included

1× AN male-to-male adapter — choose Union (same size) or Reducer/Expander (size change)

Sold individually. For joining two hoses you typically need one union; for size changes select the exact from→to size below.

Add PTFE AN Hose Ends Add Install Tools Shop Related AN Adapters Add a Gauge Port

Choose your size

Type	Common Sizes	Typical Use
Union (same size)	AN-4, AN-6, AN-8, AN-10	Join two hoses; extend a line; inline service coupler
Reducer	AN-8 → AN-6, AN-10 → AN-8, etc.	Step down to smaller component ports
Expander	AN-6 → AN-8, AN-8 → AN-10, etc.	Step up for higher-flow sections

Tip: Keep AN size consistent with the narrowest part of your system, or intentionally upsize where you need extra flow.

Leak-resistant AN flare interface for reliable service in EFI fuel systems.
Cleaner plumbing: replace stacks of tees/adapters with one precise union or reducer.
Serviceable & modular: makes line extensions and component swaps painless.
CNC-machined, anodized aluminum: durable finish—use aluminum AN wrenches to protect it.

Where these adapters shine

Joining two shorter PTFE AN hoses into one clean run.
Adapting component ports (regulator, filter, rail) to your line size.
Creating a quick inline service point ahead of a filter or regulator.

Specs

Ends	AN male × AN male (flare)
Types	Union (same size), Reducer, Expander
Material/finish	CNC-machined aluminum, anodized
Primary use	Fuel & fluid plumbing (EFI fuel, oil/trans cooler lines)

Important: For the systems above. Not for brake lines or power steering.

Install tips:

No sealant on AN flare threads. Seal occurs at the 37° flare faces.
Hold the body with aluminum vice jaws and tighten using an aluminum AN wrench to avoid marring.
Keep fittings to a minimum: unions are great for joining lines, but avoid unnecessary stacks to reduce potential leak points.
For EFI systems, run a 10 micron or finer (≤10 μm) filter on the pressure side and pressure-test after assembly.

PTFE hose tip: wrap the cut area tightly with tape before shearing; remove tape after seating the olive/ferrule. Full guide: PTFE Hose & AN Fittings Install Instructions.