Bigclive shows us what is inside a Arbra Dynamite Exploder.  The unit is completely powered by the turn handle. It is actually quite nice since it will indicate that the circuit resistance is when the handle is spun. The max firing voltage is around 1000 volts. To fire you simply press the fire button as turning the handle while pressing the fire button. When the fire voltage is reached the unit dumps the built voltage onto the output to allow any pyro devises to be fired.