We know that the requirements for a fiber optic connection and a copper connection differ significantly. While two copper conductors can be joined directly by a solder or by connectors that have been crimped or soldered to the wires, the key to a fiber connection is the precise alignment of each fiber core. And such an alignment is achieved by two precision components—the ferrule within each connector and the alignment sleeve within each adapter. On the one hand, most connectors are based on a 2.5-millimeter-diameter ferrule, in which the fiber is located. The ferrule both secures and aligns the fiber. On the other hand, inside each fiber optic adapter is the alignment sleeve. Its purpose is to bring together the ferrules of the two connectors being mated within the adapter’s sleeve and at its approximate midpoint.