new old stock Mullard vintage British made military issue EF91 CV4014 tubes. These are from the original factory crates and individually boxed as shown. These have halo getters, with military labels and the Mullard "R" code indicating they were made by Mullard in Mitcham, Surrey, England.
This item is shipped from Britain, in North America or Asia please allow 2 to 3 weeks for delivery.
These are tested for plate current and transconductance at normal operating voltages on a high precision AVO VCM163 tube tester.