Observe the 4mm banana plug logo or symbol
The name of this 4mm banana plug comes from its slightly bulged shape. It is very convenient to insert the hole on the front of the multi-purpose socket mentioned above, and a very large contact area can be formed after insertion.
This feature makes it a priority to be used in high-power output equipment to connect speakers and receivers/amplifiers. Sometimes you can see banana plugs divided into two groups, called "dual banana plugs", but not all equipment (especially speakers) can be used.
The symbol indicates the rated current/or power to guide users to avoid overloading. Observe that the 4mm banana plug logo or symbol should be durable and legible. Do not use silk screens and paper stickers that can be easily erased. Anti-electric shock protection is a key safety index to ensure that plugs, sockets and converters will not cause electric shock accidents to users and others under normal use, and even some accidents.
When the plug is fully or partially inserted into the socket, the live part of the 4mm banana plug should not be touched; any pin of the 4mm banana plug should not be inserted into the live socket of the socket when the other pins are in the reachable state. Plug sockets and converters with protective doors should be able to prevent single poles or probes from being inserted.