ProSNS F type connectors use a patented, removeable plastic sleeve guide designed to assist with the insertion of the cable center conductor to simplify the installation. As the cable center conductor is inserted into the back end of the connector, the removeable plastic guide is pushed forward and out from the front end of the connector. When the guide is completely pushed out from the front of the connector, it will detach and fall out. This design feature is to guide the insertion of the cable and to help identify when the cable center conductor is fully and properly inserted into the connector.
A patented internal O-ring at the base of the nut ensures the seal of the connector.