Frequency Converter 110v/120v 60Hz to 220v/230v/240v 50Hz, 1kVA Step-Down & Step-up Frequency & Voltage Converter

What's the power rating of this converter?

Can this vary the Hz or is it either 50hz or 60hz?

What is the output waveform of the system? if true sine wave, what is the total harmonic distortion(thd) rating at full load?

Can this machine convert 220v 50hz single phase to 220v 60hz? i brought dryer 220v 60hz from usa and use it 220v 50hz in thailand and it does not work