Don’t require power plug adapter while traveling from Japan to United States of America (US) USA.

Here's why you do not need an adapter

The outlet and plug type used in United States of America (US) USA are A and B and in Japan are A and B and they are compatible with each other.

Japan

In Japan, outlets of type A and B are in use.

Type A

Type B

United States of America (US) USA

In United States of America (US) USA, outlets of type A and B are in use.

Type A

Type B