How to Identify Fibers in High-Count Cables (>12 Fibers) For cables with more than 12 strands (e., 48, 96, or 144 fibers), the industry uses a “Tube and Fiber” system. The 12-color sequence is applied twice: first to the outer Buffer Tube, and then to the individual Fiber inside it. Critical Exception: Outdoor cables are almost always black (for UV resistance), regardless of the fiber inside. For these, you must . Fiber optic color codes provide the essential identification framework that enables fiber technicians and network professionals to manage complex optical network installations efficiently.