The Hirose JR-S is a mounting screw accessory for the JR series of circular connectors. It is specifically listed for use with JR series connectors and is the designated screw for the JRC21BP-26S receptacle. These screws secure the mating halves together, providing the mechanical retention needed in panel-mount and cable-to-panel applications where vibration or cable strain could otherwise separate the connection.
These screws are designed for the JR series connector family. The specific application note calls out the JRC21BP-26S as a compatible mating half. When ordering, confirm the screw thread and length match the panel thickness and the receptacle's threaded insert. The JR-S is a replacement or spare part — it is not typically included with the connector itself, so order separately when building a harness or servicing a field installation.