What kind of sockets do hotels in Japan have?

The plug in Japan is shown in the picture.

So two plugs can be used in common, but three plugs can't.

There is no voltage converter, you can look at your charger, which directly indicates the applicable voltage range. The range of general mobile phone and camera chargers is adaptive in100-250 V. This charger can be used directly. The voltage in Japan is 1 10v. If it is not within the range, voltage conversion is required.

The connectors of general electronic products and the pins of electrical appliances are called plugs. Plug and socket of household AC power supply, which has a male connector protruding in the form of a rod or a copper plate, and is physically inserted into a female connector type power supply socket with a groove or a concave hole. Size is an important technical requirement, which is related to whether plugs, sockets and converters can be used safely and meet the requirements of universal interchangeability to avoid wrong insertion. The unqualified size will affect the user's use or cause hidden dangers such as poor contact and wrong insertion, damage the equipment and cause fire and electric shock accidents.

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