Here is a super rare NOS new in box Mullard ez81 6ca4 made for Telefunken.
Absolutly perfect , beautiful, top conditon and perfectly balanced, within !
This is the perfect rectifier.
Tests results : 116% 115%   so extra strong too.

code 8t1 B1K3

This is probably the most sought after ez81, very early construction  with square getter  and asymetrical plate construction like made in the 50's.

It's an  8t1 model, made in Great Britain at the Famous Mullard Blackurn factory the third week of november 1963.

It was made for Telefunken for German market and wears the telefunken Label which is quite rare.

Provided with its original Telefunken box.
NOS NIB never used.
       

This is real gold for a vintage Vox AC15 AC10 or any early British amp of this era and any other and later ones too, of course.

I COMBINE SHIPPING ,  SO PLEASE HAVE A LOOK AT MY OTHER ITEMS AND SAVE .
             

These tubes has been tested with a first tester  with my Jackson 648S  for

Leakage

Filament

Circuit

Shorts

Plate

Life test...

The Jackson 648. It is definitely one of my favorite tube testers. While it does not employ a mutual conductance test circuit, it does use an advanced emission circuit that applies separate element voltages to each tube element, and separate load circuits are also used. “These voltages and loads have been carefully selected for each tube to meet most ideally the normal operating condition of the tube.” (Source: 1950 Jackson catalog.)

In my experience, the Jackson circuitry is very effective, and often will surprise you with accuracy that approaches Hickok’s coveted “mutual conductance” test method. ( Source tubesound web site.)

I do my best to test and describe the tubes the best I can.

Note that test results may vary from one tester to an other so this must be taken as an indication, although my Jackson is regularly tested for calibration.

 Photos are part of the description you get what you see.

Thank you for your interest.