Promotech Lizard is a portable, programmable, trackless welding tractor designed to produce consistently high-quality welds. It can be programmed in continuous or stitch welding modes. Welder-friendly two-function buttons enable storage and reproduction of up to 40 different welding programs for various joint configurations and multi-pass, multi-layer welds. Constant, continuous, and repeatable travel speed enables weld bead geometry that is exact to the required specifications, thus reducing costly over welding and decreasing filler metal usage, substantially. The oscillator allows for precise control of weave width, weave speed, and left/right side wall dwell and is particularly useful for vertical welding.