The free hand provided the path for current, conducting the electricity to the bottom's skin. Dragon noted that the top could also feel some stimulus. He demonstrated the effect of electricity on metal, such as nipple rings. He showed how a muscle stimulator like a TENS unit can cause the muscles to jump involuntarily. Dragon pointed out that the charge doesn't have to hurt.
Most devices have an intensity control that allows the top to vary the strength of the kick.
After the workshop Dragon demonstrated the feel of the implements on volunteers. A good deal of flirting went on at the demos. Interest was so high that I didn't get a chance to check it out there. My electro-enthusiast friend offered to demo his devices for me, so I took him up on this at a play party at the Wet Spot. He briefly exposed me to a violet wand, a TENS unit precursor, a bug zapper, and a hand cranked magneto generator.