The thing melted itself. It also burned through its hot glue insulation. The real rub is that the internal driver is only rated for 2,000 Volts, assuming this is RMS voltage, its peak would be 2,800 Volts, and after entering the bridge rectifier circuit would be 5,600 volts. SO 6 kV! WHY IS IT RATED FOR 25 kV?!
The capacitors are only rated for 20 kV, and the diodes are only 1/4" long. Given the breakdown of air is generally held to be 20 kV PER INCH (humditity / temp depenedent). The diodes couldn't possibly be rated for even 10 kV! They are standard T70A type diodes.
Would have been nice to get my money back for this POS. They didn't return my email requesting a refund...
It is rated for 25KV because it produces 25KV. Your lack of electronic knowledge is surprising. The internal driver does not go into a rectifier circuit, it clearly goes into a VOLTAGE MULTIPLIER CIRCUIT, producing 25KV. Capacitors have double the voltage rating when they are in series, making them ok for up to 40KV, not 20. Your unit burned out because of the way you grounded/powered it, contrary to the instructions, allowing HV to bleed back into the unit. Your request for a refund was turned down because you were 7 months beyond the warranty - and you were emailed this info.