Ningbo Qiaopu Electric Co., Ltd. explained plugs meaning

The plug generally refers not fixed. Plug with positive contact with body known as the male plug; called with negative contact plug female plug. Outlet generally refers to fixed (half of the panel or chassis). Outlet with a positive contact with body called public outlet; socket with negative contact body called Jack.
When the the connector two halves distinction no fixed and non-fixed (such as cable connectors), you can distinguish the contact form, can be said with positive contact body plug with negative contact body said socket.
When the the connector two halves fixed and not fixed distinguish brought contact with the body nor Yang negative distinction, two halves of the connector on regardless of plugs and sockets.
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