17 Insulators for electric cables and conduits in the nature of electrical insulators; plastic tubes for protecting electric cables; cable protective sleeving in the nature of cable bridges of rubber for protecting cables, plastic tubes for protecting electric cables, electrical insulators made of rubber, and sleeves of rubber for protecting parts of machinery; structures of plastic, namely, plastic tubes for protecting electrical cable and conduit connectors; flexible tube connections and screw connections for flexible tubes of plastic, all in the nature of non-metal fittings for flexible pipes; fittings of plastic for articulated chains and pipes in the nature of non-metal fittings for pipes, namely, storage and guide channels, support rollers, conductive inlets, and web subdivisions and mains lead cleats