PL spina RG-213/U MIL-Spec, Teflon PL connector, the plug is also called PL-259, the socket SO-239 (PL engl. Plug, SO engl. Socket). The designation "UHF" stems from old times when 30 MHz was considered "Ultra High Frequency"... (see english language Wikipedia article about the UHF connector. PL plug, standard