The BU-00260 is a BNC female to dual banana plug adapter. Typically used for adapting coaxial cables to laboratory equipment (oscilloscopes, signal generators, etc).
The BU-00261 is a BNC male to dual banana plug adapter. Typically used for adapting coaxial cables to laboratory equipment (oscilloscopes, signal generators, etc).
The BU-P5319 is a BNC female to RCA plug adapter. Useful for audio signal applications, like making BNC male connectors compatible with RCA jack connections.