The main reason for designing two additional round holes on the flat power plug is to ensure safety when using. When the plug is inserted into the socket, the flat plug with two round ends will make contact with the raised part inside the socket. This fit helps the plug to be held tightly and stably, does not cause looseness, and reduces the risk of electrical short circuit when used.

Not only ensuring safety, the two round holes on the flat power plug also help manufacturers in sealing, making it easy for users to check the condition of the product. In addition, drilling two small round holes has really helped manufacturers save a significant amount of raw materials.