The 4 Svetlana 6550C tubes in this lot all have dual dish getters with square plate holes. The gold print on the glass has the Svetlana Electron Devices (SED) logo and reads "6550 C Made in Russia" with the 1997-99 date codes and the OTK factory code etched in the glass. These tubes were made when the Svetlana name was still owned by the St. Petersburg factory (before they lost the rights and were forced to switch to the "Winged C" logo).