For example: Agilent E4440A or Anritsu 68369
Adapters
Adapters are devices or connectors used to facilitate compatibility and connection between different types of equipment or components, enabling seamless integration and functionality.
Keysight / Agilent 85130H
Test Port Adapter Set, 1.85 mm to 1.85 mm
Manufacturer: Keysight / Agilent