Powered by two AA batteries, this delivers of the order of 3,000 volts to any hapless flying insect and can also be used when they perch in casual fashion on the walls. A brief spark and they fry.
I wondered what would happen if you touched the grill yourself (it does say not to do this). Mindful of electroshock torture and tasers, I debated wimping out for a while before finally pressing the button and proceeding to zap the side of my hand (this guy was braver).
There was a bright blue spark and a sharp zapping noise - and I have to say it hurt a bit. More like a burn than an electric shock: but I wouldn't fancy prolonged contact.
Here's a guy ('Backyard Armory') showing you how to convert The Executioner into a stun gun.
This is illegal in the UK. Having watched the video I immediately noted some design improvements: the ends of the steel probes should be filed to points both to improve penetration and to increase the electric field (and therefore the applied voltage); also, his assembly is not very robust and would probably just break if used for real - the high-voltage circuitry should be embedded within a much more rigid container.
Well, we talk big but so far not a single flying thing has been harmed by The Executioner!