How to distinguish the positive and negative poles of a Japanese two-pin plug?

Japan mostly uses parallel 11. Buy a multi-function conversion plug and you can switch between parallel and figure 8. But one thing to note when going to Japan is that the voltage in Japan is 110V, so it’s best if you go there Bring an extra transformer. Depending on your electrical appliances, if your electrical appliances are 220V, you need to bring a 110V to 220V converter to Japan. This way you can use it with the conversion plug of your travel plug.