3-1/2″ x 3-1/2″ x 7 gauge (.188″ wall) square steel tubing is manufactured from ASTM A500 steel, a cold-formed carbon steel specification designed for heavy-duty structural applications. This hollow structural section (HSS) features a large square profile with a thick wall, delivering excellent strength, rigidity, and durability for demanding construction and fabrication projects. Typically produced in Grade B, it offers superior weldability, consistent dimensional accuracy, and reliable performance in industrial environments.

Applications:
3-1/2″ square steel tubing (7ga) is commonly used in:
• Heavy-duty structural frames, supports, and columns
• Industrial machinery bases and equipment stands
• Gates, railings, and security structures
• Automotive and trailer chassis components
• Load-bearing fabrication projects
• Structural bracing in commercial and industrial construction

Advantages:
• High strength: Thick wall (.188″) supports heavy loads and resists deformation
• Durable construction: Ideal for demanding structural and industrial applications
• Excellent weldability: Compatible with MIG, TIG, and stick welding
• Versatile fabrication: Can be cut, drilled, and modified for custom projects
• Consistent quality: Manufactured for precise dimensions and reliable fit

Summary:
The 3-1/2″ x 3-1/2″ x 7 gauge ASTM A500 square steel tube is a heavy-duty structural material designed for high-strength applications. Its thick wall, combined with excellent weldability and durability, makes it ideal for reinforced frames, supports, and load-bearing structures in industrial and construction settings.