Japanese power points are compatible with the two-pronged plugs commonly found in America. Many power points do not have the third hole for the grounding pin, so try and source an adaptor without a third prong. Hotels such as The Vale Niseko offer the complementary use of adaptors for in-house guests. Voltage in Japan is 100 V, which is lower than most regions of the world. Invest in a power converter to use your appliances safely.