A Red/Black connector terminal banana plug is a type of electrical connector that is used to make temporary or permanent connections between wires and circuit components. These connectors typically have a banana-shaped plug on one end and a set of spring-loaded terminals on the other end. The connector usually has two different colors, red and black, to indicate positive and negative terminals respectively.

These connectors are typically gold-plated to provide a low-resistance and corrosion-resistant connection. The 4mm plug size is a standard size and can be used with a wide range of equipment. They are often used in laboratory and test equipment, audio/video equipment, and other electronic devices.

The term "binding post" refers to the spring-loaded terminals on the back of the connector which allow for secure and removable connections to be made.

Speaker Terminal Binding Post Power Amplifier Dual 2-way Banana Plug Jack Black and Red Plastic Shell