NOS Marconi by Mullard ECC81 / 12AT7 Halo getter Valve/Vacuum Tube - AVO Tested

B5E3 date code, Blackburn 1965 manufacture. AVO NOS Specs: IA = 10.0 GM = 5.5. Valve 1: A1 8.6 4.8. No leaks or shorts / gas, solid base, shiny pins.

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