AN 4 aluminium

Weld-on AN 4 aluminum bung for clean and secure installations

Connect like a pro—no adapters, no hassle

This weld-on AN 4 aluminum bung is exactly what you need if you're setting up a fuel tank, radiator, or oil reservoir and want a clean, direct AN line without weak spots. Made from high-quality weldable aluminum and precisely machined, you simply weld it to your part and it's ready for a flare AN4 fitting—no extra steps, no nonsense.

What does AN 4 mean and why is it so widely used?

The AN standard stands for Army-Navy. It was originally developed by the U.S. military to ensure strong, leak-free connections in aircraft and military vehicles. Its proven reliability led to its adoption in motorsport and performance automotive builds. The number 4 refers to a tube size of 1/4”, perfect for fuel or oil lines in high-performance setups.

Why choose this AN 4 aluminum bung?

• Welds easily to any aluminum part with standard welding gear.
• Fits AN4 flare fittings, one of the most trusted standards in motorsport plumbing.
• Precisely machined to ensure a tight, leak-free seal.
• Compact and lightweight, ideal for tight spaces or clean engine bays.
• Professional, clean finish that matches the quality of your build.

Built for demanding projects and long-term reliability

Whether you're building a fresh AN system or upgrading an older setup, this bung gives you a solid foundation. Weld it exactly where you need it, thread your fitting in, and you’re good to go. It’s a straightforward solution for fuel, oil or coolant lines in modified cars—no improvisation, no guesswork.

Trusted, tested, and ready at Weldracingparts

We’ve been fabricating and supplying real-world parts for people who build with passion. We know you want things that work, that install without drama, and hold up under pressure. This AN 4 aluminum bung delivers. And if you’ve got questions, we’re here to help without wasting your time.

Ready to order? Add it to your cart

If this is what you need, add it to your order and keep building. And if you’re not 100% sure, drop us a message—we’ll help you figure it out so you can keep moving forward with your build, your way.