Scarce direction-finding accessories for the T 1000/ T 1000 CD World Receiver. 

According to its instructions for use, "The direction-finding equipment for the T 1000 and T 1000 CD Global Receiver consists of the PK 1000 cross-type ferrite antenna and the PV 1000 adapter. It is designed as a navigational aid for ships or boats that are not required by law to have full-scale commercial direction-finding equipment."