Over 80 percent of this fish’s body volume is taken up by its electrical organs. These are in the form of plates consisting of white, jellylike areas divided by harder tissue. There are about half a million plates in the body and they can generate an electrical discharge of at least 550 volts with a current of 2 amps, producing a kilowatt of power. Each and every stun keeps up for just an exceptionally short time; about three-thousandths of a second. But electric eels can produce as many as 150 shocks in a hour,with no fall-off in output.

The ability of electric rays to inflict shocks was well known centuries before the power of electricity was understood. Their electrical output is about 220 volts; much less than that of the electric eel; so they do not represent a serious danger to humans.

While an electrical shock from one of these catfish will not be powerful enough to kill a human, it is strong enough to stun prey. This is significant resulting from the fact that the aforementioned catfish are not equipped to swim swiftly and so prey might effectively break from them.