BNC Bayonet Neill Concelman connector, (sometimes erroneously called a British Naval Connector or Bayonet Nut Connector,a type of connector used with coaxial cables such as the RG-58 A/U cable used with the 10Base-2 Ethernet system. The basic BNC connector is a male type mounted at each end of a cable. This connector has a center pin connected to the center cable conductor and a metal tube connected to the outer cable shield. A rotating ring outside the tube locks the cable to any female connector. BNC T-connectors (used with the 10Base-2 system) are female devices for connecting two cables to a network interface card (NIC). A BNC barrel connector allows connecting two cables together. BNC connectors can also be used to connect some monitors, which increases the accuracy of the signals sent from the video adapter.