Black Steel Rectangle Tubing

3/8'' Thick, 3'' x 6'' x 20', Black Steel A500

A heavy-duty, high-strength structural steel section built for demanding construction, fabrication, and industrial applications. Manufactured from ASTM A500 black steel, this rectangular tube provides exceptional rigidity, outstanding durability, and reliable performance wherever superior structural support is required.

High-Strength Structural Performance – Made from ASTM A500 steel to ensure consistent quality and dependable load-bearing capability for critical builds.

Durable Black Mill Finish – Offers protection during handling and fabrication while maintaining a clean, professional appearance.

3/8 in. Wall Thickness – Enhanced strength and rigidity for heavy-duty structural, industrial, and fabricated components.

Precision 3 in. x 6 in. Profile – Accurate dimensions deliver stability and uniformity for reinforced framing, supports, and engineered structures.

20 ft. Length – Ideal for medium-to-long structural spans while minimizing the number of joints required.

Excellent Fabrication Qualities – Suitable for MIG, TIG, and stick welding, and easily cut, drilled, or machined for project customization.

Consistent ASTM-Certified Integrity – Manufactured to strict standards to ensure repeatable structural performance in commercial, industrial, and agricultural use.

• Heavy structural framing and supports

• Equipment and machinery fabrication

• Trailer, platform, and rack construction

• Agricultural, industrial, and commercial building projects

• Custom metalworking and engineered fabrication

• Material: ASTM A500 Black Steel

• Wall Thickness: 3/8 in.

• Dimensions: 3 in. x 6 in.

• Length: 20 ft.

• Type: Structural rectangular tubing

• Finish: Black mill finish