The Katana is the long sword of the samurai.
The Taser Katana is an interesting little device. It consists of two fine wires strung in parallel, mounted to a plastic centerpiece. The whole assembly very much resembles (and in fact may be adapted from) the corona wire assembly from copy machines.
The central mount is a piece of slightly flexible plastic, about the diameter of a piece of spaghetti, and perhaps 15 inches in length. From each end, a small flange extends, with a tab and one end by which it is held. Parallel to the centermount and ot each others, the wires are strung between the flanges. The centerpeice is nonconductive and the wires carry the taser charge. The whole assembly, not including the taser generator unit, might weigh as much as ten grams, and seen endwise, is almost invisible.
This tool has the advantage that it is not gun-shaped, and the unit that generates the taser charge may be kept in a pocket. All that is necessary is that the two wires contact the skin of the adversary.
The technique I have seen most often used is to have one person walk behind another, the person behind clips the generator unit to the belt of the person in front, and hands the insulated handle of the taser katana to the person in front, with the person in front reaching back over the top of his shoulder as if he were scratching an itch. When he has the tab gripped safely, the other person activates the generator, and the person who has it whips it at the target. To attempt to block it is to hasten contact, and to fail to block it means that you get hit on the head with the stunning voltage.
Beware, this is exclusively the tool of spies or criminals.