How dangerous the dart is will depend on Amps not volts, You could take 100,000,000 volts and be just fine if there was no amps. There are ways of course to increase or decrease the amps. However by increasing amps you lose voltage and the opposite is also true. So It all depends on what you want . You could hook up a capacitor and a small transformer and make it very deadly. But anyways. I dunno if i accidnetly posted what i wanted to say about five minutes ago somewhere else or what but. From what i saw on the link i was slightly confused, being that it was stated that the dart could shock for ten seconds? Was that not a capacitor? A capacitor exerts all of its energy at once in one big blast, like for instance the draw the flash of a camera would create, which is what the capacitor i plan to use is for. The shock would be instant and it could be possible to get a second shock MAYBE without recharging but it would be very light. But up to the user you can use them for fun or set them up to be deadly with some minor mods. Radio shack would have everything you'd need for it. But the camera flash capacitor out of a disposable is not deadly, and can be recharged just by touching the two prongs back to where they came from and pressing the button that would normaly charge the flash for the camera, it will look like a little gold square if you've taken it apart, be sure not to touch those two wires while charging though, because that will be a sustained shock lol.