They are the new Russian tube from New Sensor.
New Sensor acquired the rights to both Mullard and Tungsol Trademarks and are now marketing the same Sovtek and Electro Harmonix tubes with new names.
The original Svetlana trademark is also owned by them, meaning the current releases of Svetlana are NOT from the St. Petersburg plant, but rather the Reflector plant in Russia.
Original Svetlana tubes are still available under the trademark "Winged C" and are currently marketed by Antique Electronics in AZ.
Whatever you do, don't get in a bidding war at EBAY over "Mullards" that are new Russian tubes. The Russian tubes are OK, but easily obtained and very reasonably priced.
New Sensor acquired the rights to both Mullard and Tungsol Trademarks and are now marketing the same Sovtek and Electro Harmonix tubes with new names.
The original Svetlana trademark is also owned by them, meaning the current releases of Svetlana are NOT from the St. Petersburg plant, but rather the Reflector plant in Russia.
Original Svetlana tubes are still available under the trademark "Winged C" and are currently marketed by Antique Electronics in AZ.
Whatever you do, don't get in a bidding war at EBAY over "Mullards" that are new Russian tubes. The Russian tubes are OK, but easily obtained and very reasonably priced.