10401920 - Tweco Classic 4 MIG Gun, 400A, 10ft, Miller Connection

Industry-Standard Heavy-Duty MIG Welding Gun

The Tweco Classic No. 4 MIG Gun (10401920) represents the gold standard in air-cooled MIG welding torches. Designed for industrial environments where reliability and durability are paramount, this gun is rated for 400 Amps at a 60% duty cycle using CO2 gas. It features a 10-foot cable assembly, providing adequate reach for bench work and standard fabrication cells without the clutter of excessive cable length.

This specific model is configured with a Miller-style rear connection, allowing for direct connection to Miller wire feeders and power sources without the need for additional adapters. The Classic No. 4 series is renowned for its robust construction, featuring a heavy-duty metal jacketed conductor tube and a rugged handle that withstands the rigors of daily shop use. Maintenance is straightforward, utilizing the widely available Tweco 14 Series contact tips, 24 Series gas nozzles, and 44 Series diffusers, ensuring that consumables are always easy to source.

Ideal for heavy equipment manufacturing, structural steel fabrication, and general industrial maintenance, the Tweco Classic No. 4 minimizes downtime through its field-repairable design. The cable is engineered to resist abrasion and cuts, while the trigger mechanism is tested for millions of cycles. Whether running solid wire or flux-cored wire, this gun delivers consistent arc performance and wire feeding.

Key Technical Specifications

• Amperage Rating: 400A (CO2) / 300A (Mixed Gas)


• Duty Cycle: 60%


• Cable Length: 10 Feet


• Rear Connection: Miller Style


• Wire Capacity: Up to 5/64" (2.0 mm)


• Cooling: Air Cooled