1. Digital tube accurate display, encoder (not potentiometer) regulation is more accurate and stable, longer life 2. Single and double pulses are adjustable, spot welding counting, synchronous triggering, power-off saving 3. 41A thyristor version can control transformers below 1000W, 100A thyristor version can control transformers below 3000w 4. This control board adopts double-sided welding, integrated into a board with more reasonable component layout, in order to be easier to install on the machine casing. 5. foot pedal anti-shake function is added, one spot welding is completed once it collapses, preventing factors such as poor switch contact from causing mis-spot welding! It must be powered by an AC transformer (AC 12V-17V power supply). It cannot be powered by a DC power supply! It's DIY kits, needs to finish by yourself. Color: Red Material: ABS Package Contents: 1 x 100A Welder Controller Board