high and low frequency connectors and connector cable assemblies; fiber optic connectors and fiber optic cable assemblies; optical signal transmission apparatus, optical signal distributors, switches and amplifiers; installation apparatus for communications engineering, data systems engineering and industrial electronics; namely, crimping inserts, locking troughs for housings and mounting frames; components and parts for communications engineering, data systems engineering and industrial electronics, namely connection boxes, connectors, flush and surface mounted boxes, cover plates, connector housings, cable reliefs, sockets, and coding and non-locking apparatus; apparatus for communications engineering, data systems engineering and industrial electronics, namely automatic multi-switches for telephone sets, surge suppressors, lightening arrestors, line matchers, line terminations, test headsets, test handsets, test telephones, test apparatus for communications systems, modems, PABX's, and two-way intercoms; industrial control apparatus for controlling environmental and ambient conditions, temperature, light intensity, machine motion, and voltages; and electronically and electrically controlled alarms for detecting and signaling fault conditions