2pcs High Voltage Generator DC 3v-6v to 400kV 400000V Boost Step-up Power Module High Voltage Transformer

Very potent. Works as advertised

These work perfectly. At 5V they draw about 1-2A and will arc about 1-1.25”. That suggests that they are more like 200,000V, but still loud and very cool. Trivially easy to use and wire up. Cannot speak to durability, but so far, they haven’t fried.

Cumple con lo especificado

It's got a nice loud pop. I discovered that making the contact tips bigger around and adding a capisitor. No I don't have anyone to test it on. Hmm I might have to try it on myself.

it can shock you alright

It works, and produces a nice spark (powered with 4 AA batteries), but that spark won't jump across more that about a 1/4 inch gap. There is no way this device produces a 400KV output, its more like around 20KV. I won't return it because Its cheap enough to keep and play around with. But, buyer beware, the seller is giving very inaccurate specs about this product.

I am a Physics teacher who needed a cheap high voltage device for some of my class demos. This works great! No instructions come with it so red is positive input, black is negative (6 volt max DC) Don't run it too long or it'll burn it out I'm sure but cheap enough to get more.

Put these in harbor freight electric flyswatters and now they're much more powerful. They make it arc between the screens like a taser. Much more enjoyable bug swatting experience

i made something amazing with these and theyre fantastic

Running off a 3.7V Lion and tested the output voltage with a meter specifically designed for high voltages (electric cattle fences). Doesn't come anywhere near 400,000. It could barely reach 4000. So yeah, not quite as advertised.