This is the only known Russian threadless insulator style. It has been assigned to CD 546 on November 2024 and is listed on the NIA site. I know of 5 examples that have been found and 3 are in USA. My contact in Russia has recently turned 18 years old and can no longer acquire these because of conscription. What I understand is that these were rescued from an ancient building that is in an undisclosed location in Russia. No other units have been located at this time and it is unknown where the other 2 examples are (possibly now in Belarus). I will post more information about these if I get any.