G.E.C (Genalex) 6X4WA CV4001 Rare 1958 Black Plate Square Getter MINT NOS NIB Premium CV4005 Rectifier Marconi Osram Hammersmith Prod. England - Plug and Play Ready to Use Some tubes have completely unusable

Some tubes have completely unusable boxes due to age

Mullard Whyteleafe "A" Plant Date Codes

Another hand written serial number on the side and text PM25525-1

Side note of importance: I volume match the low and high gain settings on my Mjolnir 2 with the use of a sound level meter and test tracks

Brand New MINT NOS Rare 1967 Mullard CV4109 Military tubes

G.E.C (Genalex) 6X4WA CV4001 Rare 1958 Black Plate Square Getter MINT NOS NIB Premium CV4005 Rectifier Marconi Osram Hammersmith Prod. England - Plug and Play Ready to Use Some tubes have completely unusableRare Brand New, MINT NOS NIB 1958 G. E. C (Genalex) 6X4WA CV4001 Black Plate Square Getter Tubes. In white military boxes with brown cigar rolls. Made in England. All tubes have same date batch code PG, PE or QC KB Z from MO (Marconi Osram) Valve Company, Hammersmith Plant. CV4001 premium grade version of the Black Plate CV4005 6X4WA 6063 is one of the best from Genalex in the 6X4 types. These tubes are one of a kind. No refunds, exchanges or tube