The “12c” designation in the **12c single mode fiber optic cable** refers to a specific cable configuration that typically includes 12 color-coded fibers within a single jacket. This small diameter core, typically around 9 microns in diameter, allows only one mode of light to pass through, resulting in a narrower beam of light. There are two main types of fiber optic cables: single mode and multimode. That makes picking between single mode and multimode fiber optic cables an. Two popular types of optical fiber cables are 8-core optical cable and 12-core single-mode indoor fiber optic cable.