What do FC and SC mean in fiber distribution boxes

FC and SC are types of fiber optic connectors used to join optical fibers in distribution boxes, with FC featuring a screw-on design for high-precision connections and SC using a push-pull mechanism for easy installation.SC Connector (Subscriber Connector)The SC connector is widely used in telecom and data center applications. It has a square body with a 2.5 mm ceramic ferrule and a push-pull latch mechanism, which provides a secure connection with a positive click when seated. SC connectors are easy to install and remove, making them practical for structured cabling systems, medium-density panels, and environments where frequent plug-and-play is required. They are compatible with both single-mode and multimode fibers and are valued for their robustness and low insertion loss in general-purpose networking .FC Connector (Ferrule Connector)The FC connector features a round metal body with a screw-threaded coupling, which ensures a highly secure and vibration-resistant connection. It also uses a 2.5 mm ferrule but requires careful alignment during installation. FC connectors are typically used in telecom systems, optical distribution frames, measurement equipment, and single-mode laser applications, especially where mechanical stability and precision are critical. While reliable, FC connectors are slightly more complex to install compared to SC connectors and are gradually being replaced by SC and LC connectors in many modern networks .Key DifferencesLocking Mechanism: SC uses push-pull; FC uses screw-on threading.Body Shape: SC is square; FC is round and metallic.Ease of Use: SC is easier to plug and unplug; FC requires careful alignment.Applications: SC is common in general telecom and data centers; FC is preferred in high-precision or high-vibration environments. Understanding these connector types helps ensure efficient fiber management, minimal signal loss, and reliable network performance in fiber distribution boxes .