What he hell is in his USB charger that's worth even $50 let alone $800? And what's in his battery/switch/pump/spray nozzle design that makes it worth $40, let along $4,000?
I don't suppose the downvoter could answer a serious question?
I'm offering you a chance to larn an ignerr'nt furrigner somink! [Yeah sorry, too early in the morning after a rough night and I mix accents like some people mix metaphors]