The Keysight 16195B is a calibration kit for the Keysight RF LCR meters,  impedance / material analyzers, and network analyzers. The calibration using the Keysight 16195B is performed on the 7 mm connector plane.  The calibration kit contents include 50 Ohm termination, open termination, short termination, low-loss capacitor, and carrying case. 

• Compatible LCR Meters: 4287A, E4982A
•  Compatible Impedance / Material Analyzers: E4991A, E4991B
•  Compatible Network Analyzer: E5061B