How can these be described? Mmmmmmm.
Imagine a set of nun-chucks, but instead of being linked by chain, they're linked by a piece of cable. The wooden bits at the end are replaced by rubber grips with, on one side, a neon polarity indicator, and on the other a voltage toggle switch (technical eh?). The probes on these things are about 3/4 of an inch long and viciously sharp. Voltages are checked by placing these probes are into small orifaces in fuse panels. Jack, having a superb imagination, can think of a miriad of other orifaces to stick them into. Usually his oppos.
Many injuries have occured when used in 'nun-chuck' mode, almost always to the weilder, and never the target.
Worn casually around the neck a la doctors stethoscope, and a cautionary note to prospective greenies, never, ever, ever test voltages with them still around your neck. It'll quite possibly be the last thing you do.