Stun guns are marketed by voltage. Consumers believe the higher voltage are the most effective stun guns. However, this is not the case. It’s amperage that makes a stun gun effective. One amp will kill a person. The amperage output of stun guns is much less than that. Stun guns are usually between 2-5 milliamps. The more powerful stun devices are at the upper range. So, don’t focus on the voltage, but to the amperage. It’s always best to purchase a stun gun from a trusted seller of these devices.