411WORKS Steel Cups with Aluminum Bungs: Built for Fabricators Who Demand Precision

When it comes to fabrication, the little details are everything. That’s where our 411WORKS Steel Cups with Aluminum Bungs step in—machined in-house on our HAAS CNC machines using high-quality 1018 Steel and 6061 Aluminum sourced right here in North America. These aren’t generic, overseas-made parts. They’re crafted with precision and pride, right in the USA.

What They Are

• Steel Cups — Available in three variations: Deep, Shallow, and Scallop. Each style gives you different geometry depending on the clearance, strength, or design your project calls for.

• Aluminum Bungs — Available in four common thread sizes:

  • M6 x 1.0

  • M8 x 1.25

  • 1/4-20

  • 5/16-18

Together, the cups and bungs form a lightweight, strong, and versatile solution for fabrication jobs where threaded mounting points are needed.

What They’re Used For

411WORKS Steel Cups with Aluminum Bungs are designed for fabricators and builders working on motorsport, off-road, and custom chassis applications. Here’s how they get put to work:

• Roll Cages & Tube Frames: Steel cups act as precision mounting bases while aluminum bungs provide clean, reliable threaded points. Perfect for securely attaching panels, braces, and removable sections.

• Suspension Fabrication: Need a threaded mount for sway bars, end links, or brackets? These cups and bungs provide consistent strength and alignment, even under heavy loads.

• Drift/Track Builds: From intercooler piping mounts to custom bracketry, the combo allows you to add strong, serviceable attachment points without compromising weight.

• Off-Road & Overland Rigs: Ideal for skid plate mounting, body protection, and modular parts that need to bolt/unbolt repeatedly without chewing up threads.

• General Fabrication: Anytime you need a flush, strong, clean threaded insert that’s easy to weld into place, these cups and bungs make the job look pro instead of hacked.

Why These Matter

The difference is in the details:

• Strength: 1018 steel provides toughness and weldability without cracking or distortion.

• Lightweight & Corrosion Resistance: 6061 aluminum bungs keep weight down and resist corrosion while holding threads tight.

• CNC Precision: Tight tolerances ensure consistency—no fighting with sloppy threads or uneven geometry.

• Made in the USA: Fabricated in-house on HAAS CNC machines using materials sourced from North America. You’re not just buying hardware—you’re buying reliability and repeatability.

Bottom Line

Whether you’re fabricating a drift car roll cage, building an off-road crawler, or just need clean threaded mounts for a custom bracket, 411WORKS Steel Cups with Aluminum Bungs give you a pro-grade solution. Strong, clean, and built right—because the last thing you need is cheap hardware failing on a high-stress build.

Want to grab a set for your next project?

Order 411WORKS Steel Cups with Aluminum Bungs from Select Speed Shop →