VCT VT-500J - Japanese Step Up/Down Voltage Transformer Converts Japan 100 Volts To 110V OR Vice Versa - 500 Watt

I have https://www.amazon.com/dp/B000PC4JL4?th=1. I don't use it that often, but it's been working fine for me. It's pretty heavy, and I kind of wish it had a modular cord instead of one that's permanently attached. One basically useless (to me) feature is that it can be configured to either step down or step up - presumably it's just a big transformer in a box. Fortunately, the switch to change that is behind a plastic cover, so you're unlikely to accidentally flip it. There might be other options, but this one is good enough for my use.