Optical fiber splice box: A device used to connect two fiber optic cables into one longer cable. The backbone ODF usually does not contain any fiber optic splitters, and the fiber cores of the backbone cable and. A fiber terminal box, also known as a fiber distribution box, is a device used in fiber-optic communication networks to terminate, splice, and distribute optical fibers. Jumper Both ends of the jumper are movable connectors, which connect the pigtail and the device. Through termination box couplers (adapters), pigtails and patch cords are connected. Even minor physical stress, such.