How to use edm machine remove broken bolt

High Power Portable EDM Machine SFX-4000B...

1) For SFX-4000B, there is a space for storage at the bottom of power box which is convenient for managing attachments. There is a tool bag accompanied with EDM-8C, which could manage all the attachments. 2) For SFX-4000B, there is a voltmeter and a current regulating knob added on the panel of power box which increases its intuition and practicability. 3) The panel of SFX-4000B has been upgraded to touch-sensor panel with better durability and appearance. It reduces operational complexity, s...