Tweco GC-300 Copper Ground Clamp - 300 Amp (Master Pack of 24)

Reliable Arc Starts Every Time

As a welder, you know that a bad ground is the root of many welding problems—sputtering arcs, wandering puddles, and hot cables. The Tweco GC-300 Ground Clamp is the industry standard for a reason: it works. This Master Pack of 24 is perfect for outfitting a whole shop or keeping your rig stocked for the long haul. Unlike cheap steel clamps that heat up and lose their tension, the GC-300 is built with copper alloy jaws. Copper conducts heat and electricity far better than steel, meaning this clamp stays cooler and transfers more of your machine's power directly to the workpiece where it belongs.

The clamp features a strong spring that provides excellent biting force. This is crucial for cutting through surface contaminants like mill scale or light oxidation to establish a clean earth connection immediately. The jaw opening is generous, extending up to 1.5 inches, which allows you to clamp onto tables, flanges, or the workpiece itself with ease. The design is ergonomic, allowing for easy one-handed operation even when wearing thick welding gloves.

Installation is straightforward thanks to the ball-point cable connection. You simply strip your cable, insert it, and tighten the screw; the ball-point design prevents the screw from shredding the copper strands of your welding lead, ensuring a tight, high-contact connection that won't wiggle loose under vibration. Rated for 300 Amps, this clamp handles the heat of daily fabrication work without melting down or annealing the spring. Whether you are running Stick, MIG, or TIG, a solid ground is the foundation of a good weld, and the Tweco GC-300 delivers that foundation consistently.