Unlike a patch cord—which has connectors on both ends—the bare fiber end of a pigtail is designed to be permanently spliced (either by fusion or mechanical splicing) to the incoming fiber cable in the field. Instead of building a connector from scratch in the field, you simply fuse the “bare” end of the pigtail to. Fiber pigtails are simple in appearance, yet essential in function. They are the bridge between fiber optic cables in the field and the equipment or patch panels that manage them. Ensure Your Splicing Tools are Clean – #2. Set Your Fusion Parameters in a Systematic Way What is Fiber Optic Splicing and Why is it Needed? First, let us understand the meaning of the term.