The TE Connectivity 619361-1 is an SMPM measurement probe from the Pico® II series, designed for direct RF probing of SMPM interface circuits on boards or modules. It carries a gold-plated brass body and a gold-plated beryllium copper center contact — the beryllium copper gives the centre pin the spring memory it needs for repeated landings on SMPM jacks without taking a set. The gold finish across body and contact keeps oxidation off the signal path through hundreds of mate cycles in a lab or test fixture environment.
If your design can accept a standard SMPM bullet or cable-end connector rather than a probe, a TE or Amphenol RF applications engineer can suggest an active alternative; for the probe form factor itself, the 619361-1 is the end of the line.
What the Gold and Beryllium Copper Tell You
The beryllium copper centre contact is the standard choice for spring-loaded or high-cycle RF pins because it resists stress relaxation; a brass pin would take a set after repeated compression against an SMPM jack centre conductor. The brass body is fine — it is the structural shell, not the signal path — but the centre pin material is what governs the probe's useful life in a test fixture.