Abstract: A duplex adapter or duplex adapter part for a duplex plug of an optical plug-in connection includes two pairs of plug openings which are aligned to one another and into which in each case a duplex plug may be introduced from oppositely lying sides. It is formed from a housing and at least one frame which is fastened or fastenable on the housing and which projects proximally from the housing. The frame surrounds the two plug openings of an adapter side and comprises a middle portion which extends between the plug openings. A safety device for the plug side and which matches this, includes a duplex plug or a clip for creating a duplex plug from two simplex plugs, as well as an actuator for simultaneously activating unlocking pawls of both plugs.

Abstract: The invention relates to a fibre-optic plug-in connector system (10) comprising an adapter (11), in addition to individual optical plug-in connectors (13), in which a respective optical fibre terminates in a ferrule (23) and which can be respectively inserted into the adapter (11) from two opposing sides to produce an optical connection between the ends of two optical fibres. According to the invention, the adapter (11) has a plurality of parallel guide sheaths (45), which are located next to one another in an adapter housing (12) and into which the optical plug-in connectors (13) comprising their ferrules (23) can be inserted from both sides. To achieve an extremely simple, space-saving construction for a plug-in connector system of this type, the adapter housing (12) is composed of several separate, interconnectable parts (17, 18), between which the guide sheaths (45) are held with a degree of play.