OPTICAL FIBRES, OPTICAL FIBRE CABLES, AND OPTICAL FIBRE CONNECTORS; ELECTRICAL INSTRUMENTS FOR USE IN THE INSTALLATION, TESTING AND REPAIR OF OPTICAL FIBRES, OPTICAL FIBRE CABLES AND OPTICAL FIBRE CONNECTORS; CONDUITS FOR RECEIVING OPTICAL FIBRES AND OPTICAL FIBRE CABLES, OPTICAL FIBRE ELECTRIC INTERFACES; OPTICAL FIBRE SYSTEMS COMPRISING OPTICAL FIBRES, CONDUITS, CONNECTORS AND ANCILLARY PARTS; FITTINGS; NAMELY, CONNECTORS, CONDUIT CLOSURES, CONNECTION BOXES, GLANDS, COVERS, PROTECTIVE SLEEV...