Abbreviated as OTB, fiber optic termination box is mainly used for the fixing of optical cable terminals, the fusion of optical cables and pigtails, and the storage and protection of remaining fibers. They are the bridge between fiber optic cables in the field and the equipment or patch panels that manage them. Get the wrong connector type, the wrong polish, or skip proper fusion splicing technique—and you're looking at elevated signal loss, increased back reflection, and a. It is used in a terminal box to connect the optical fibers in the optical cable, and to connect the optical cable and the jumper through the terminal box coupler (adapter).