Fiber optic pigtails can be split into two categories: single-mode (yellow) and multimode (orange). 5/125 micron or 50/125 micron bulk multimode fiber cables and are terminated with multimode fiber optic connectors at one end. One end features a. Fiber Optic Pigtails are mainly categorized into single-core, dual-core, 4-core bundled pigtails, 12-core bundled Fiber Optic Pigtails, 12-color bundled pigtails, SC bundled Fiber Optic Pigtails, FC bundled pigtails, LC bundled pigtails, and ST bundled pigtails.