Bon, remetons les choses au point... ( en Anglais desolé )
Distribution "formally" informing you about the new name "Winged-C" for the formerly named "Svetlana" tubes?:
"JSC Svetlana is a Russian company that owns and operates the Svetlana factory in St. Petersburg, Russia, which has been making vacuum tubes for almost a century. These tubes have been known in the United States as SVETLANA brand tubes and had the "S" logo and/or the "Winged-C" logo (a Cyrillic C) on them. Because of a change in ownership of the former American distributor, JSC Svetlana recently lost its ability to sell vacuum tubes bearing the SVETLANA name, while maintaining the ability to sell the tubes bearing the "Winged-C" logo in the United States and Canada."
"The Xpo-pul factory (otherwise known as Reflector) in Saratov, Russia, is an entirely different Russian company that makes vacuum tubes for an American corporation that controls the SOVTEK and ELECTRO-HARMONIC brand names. This same American corporation (NEW SENSOR) now also owns and control the "Svetlana" brand name in the United States and Canada, and is introducing a new line of Svetlana branded vacuum tubes produced in the Xpo-pul factory. The Xpo-pul factory "Svetlana" tubes are not the same Svetlana tube that you have been accustomed to over the years!" [emphasis mine]
"Rest assured that the Svetlana factory in St. Petersburg, Russia, is still producing vacuum tubes and has no plans to stop. Those tubes are available to you through CE Distribution under the "Winged-C" name."
"All current production St. Petersburg factory tubes -- and only those tubes -- do bear the "Winged-C" mark, while in the past some did not. In today's world if you want the tubes that you've come to know in the past as SVETLANA, the only way to be sure you're getting that tube is to look for the "Winged-C" mark.