12101302 - Tweco 21T-37-F Threaded MIG Nozzle 3/8 Inch Bore Flush Tip (2-Pack)

High-Performance Tweco 21 Series Threaded Nozzles

Professional welders know that gas coverage is critical for preventing porosity and ensuring sound mechanical properties in a weld. The Tweco 21T-37-F (1210-1302) is a premium threaded MIG nozzle designed to deliver consistent laminar gas flow for Tweco 21 Series front-end consumables. Engineered for use with Tweco No. 1 and No. 2 MIG guns (rated up to 250 amps), this nozzle is an essential component for light-to-medium duty fabrication environments.

The specific geometry of the 21T-37-F is optimized for versatility. The 3/8-inch (9.5mm) bore is smaller than standard 1/2-inch nozzles, allowing for better access into corners and tight joints without sacrificing gas shielding efficiency. The Flush (F) tip relationship places the contact tip even with the nozzle exit. This setup is ideal for short-circuit MIG welding, as it allows for a shorter electrode stick-out, reducing resistance and increasing amperage for better penetration, all while keeping the gas envelope close to the puddle.

Constructed from a robust copper alloy, the 21T-37-F offers excellent thermal conductivity, rapidly drawing heat away from the front end to prevent overheating and insulator failure. The nozzle is self-insulated, featuring an internal insulation material that protects the gun's neck and gas diffuser from electrical shorts if the nozzle accidentally contacts the workpiece. The coarse threads are designed to resist seizing, even after exposure to the high heat and spatter typical of industrial welding applications.

Technical Specifications:

• Series: Tweco 21 Series
• Connection: Threaded (Coarse)
• Bore Diameter: 0.375" (9.5mm)
• Tip Recess: Flush
• Compatibility: Tweco #1, #2, Mini-MIG, and compatible guns