The three main categories of pigtail connectors are RF/coaxial pigtails, fiber optic pigtails, and electrical/automotive pigtails. It's a short wire with a connector installed on one end, such as a spade or ring terminal, while the other is left bare or blank. These connectors can be a big help when you need to connect two wires. The term pigtail refers to the physical appearance of the wire, which often resembles the curly tail of a pig before it is installed. In electrical applications, it allows a device (like a sensor or switch) to be connected to. What is the similarity, and what is the difference? First, the most critical difference is the fiber connector.