What a Stun Gun Actually Does, and What a TASER Does Differently
Figures last verified
A handheld contact stun device delivers current through the skin at the point of contact. It hurts, intensely, and it does not take away the ability to move. A conducted electrical weapon that fires probes can cause neuromuscular incapacitation, meaning the target loses voluntary control of the muscles between the two probes, and that only happens if both probes connect with enough separation.
These are different effects produced by different mechanisms, and a buyer who expects the second and purchases the first has bought something that does not do what they think.
Pain compliance versus incapacitation
Pain compliance means the device hurts enough that the person chooses to stop. It depends entirely on the person's response to pain, which varies enormously and is reduced by adrenaline, intoxication, mental health crisis, and simple determination. A person who decides to absorb the pain and continue is not physically prevented from doing so.
Neuromuscular incapacitation does not ask for cooperation. Current passing through a region of the body at the right waveform overrides voluntary motor control in the muscles within that circuit. The person falls not because it hurts but because the muscles stop taking instructions. Determination is not a defense against it, which is the entire point.
Contact devices produce the first effect. Probe deployments can produce the second. The word stun appears in the marketing for both.
Why probe spread governs everything
A probe-firing weapon sends two darts on conductive wires. The circuit runs from one probe, through the body, to the other. The muscles affected are those inside that circuit.
Spread is the distance between where the probes land, and it is a function of distance to the target, since the probes diverge as they travel. At very close range the probes land inches apart and the circuit is small, producing localized pain rather than incapacitation. At greater distance the spread widens and the circuit covers more muscle mass.
There is a useful window rather than a maximum. Too close and the spread is insufficient. Too far and the probes may miss, the wires may reach their limit, or one probe may fail to connect.
Both probes must connect. One in the target and one in the air, in a wall, or dangling from clothing means no circuit and no effect at all, and the device will still make noise and light while accomplishing nothing.
What defeats a probe deployment
Heavy clothing is the most common failure. Probes must penetrate to make electrical contact, and a thick winter coat, a leather jacket, or loose layered fabric can stop a probe short of the skin. The probe can also land in fabric that holds it away from the body, which looks like a hit and is not one.
Missing is straightforward. A probe weapon is aimed like a firearm, under stress, at a moving person, usually at night. Both probes have to land on the target.
Wire breakage ends the circuit.
Range limits are real. Consumer units carry shorter wire lengths than law enforcement models, and the usable distance is a matter of feet, not yards.
One shot is common on consumer devices. Many have a single cartridge, and reloading under pressure is not realistic. Most include a contact stun capability as a backup after the cartridge is spent, which returns you to pain compliance.
What contact devices are actually for
They are not useless, and the honest framing matters more than dismissal.
A contact device produces immediate severe localized pain and a loud, visible arc. The arc itself has a deterrent effect on some people, and the pain can create a window to disengage and leave.
That window is the realistic goal. Nothing in the less-lethal category is reliably a fight-ender, and planning around escape rather than around stopping someone is the framing that survives contact with how these devices actually perform, which is covered in when less-lethal doesn't work.
A contact device also requires you to be within arm's reach, which is the range at which you are already being grabbed. That is a significant tactical cost relative to a spray, which works at several feet, compared in pepper gel, spray, foam, and stream.
Specifications that mean nothing
Voltage claims dominate consumer stun device marketing and are close to meaningless. Millions of volts appears on packaging routinely. Voltage describes the potential required to arc across a gap, not the effect on tissue, and open-air arc voltage is measured with no body in the circuit at all.
What matters physiologically is charge delivered, usually expressed in microcoulombs, along with pulse waveform and rate. Consumer packaging rarely states any of these, and when a device advertises voltage instead of charge, the absence is informative.
There is no consumer standard requiring these figures to be verified. Two devices claiming identical voltage can deliver substantially different charge.
Battery state changes output. A device that has sat in a drawer for two years on a partial charge may deliver a fraction of its rated output, and there is no indicator for this beyond testing it, which most people never do.
Testing and maintenance
Test contact devices periodically by arcing them in the air for a second. The arc should be bright, loud, and continuous. A weak or intermittent arc means a battery or internal fault.
Rechargeable units need a charging schedule the same way a smoke detector needs battery changes. A device that does not work when needed is worse than no device, because it was counted on.
Probe cartridges have expiration dates. The propellant degrades, and an expired cartridge may fail to deploy or deploy weakly.
Where this leaves the decision
If the expectation is stopping someone regardless of their willingness to be stopped, only a probe deployment with adequate spread does that, and it has multiple ways to fail that are outside your control.
If the expectation is creating pain and noise that may produce a chance to leave, a contact device does that at the cost of requiring contact range.
Neither is a guarantee, and the failure modes for both are specific and knowable rather than mysterious. The rest of that picture is in when less-lethal doesn't work, and the question of where any of it is lawful to carry is layered enough to have its own treatment in carrying less-lethal where you actually go.
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