By modifying the secondary coil on a MOT, the transformer is converted from a high voltage/low current device into a low voltage/high current metal melter. The first MOT in the video produces just over 500 amps, and the second one is capable of nearly 800 amps. Any metal that can conduct such low voltage electricity acts as a resistor between the electrode wires, and heats up due to the extreme electrical friction. A practical application of this modified transformer is shown in another video on how to make a spot welder. This way, the high current can be directed to one focused location to fuse sheets of metal together on contact.