EL12N Powertube with 12-pin steelsocket Y8A- it is made in Germany.
It is very similar to EL...

Fits to our UX8 connector
ideal for 6C33C (6S33S) Amps and strong Power supplies
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tube example (german 9´s series): DF91, EC90, EC903, EL95, 50C5
use for: PCB (PC-board) moun...

the triode system is 100% a half 12AX7 system,
therefore a cheap possibility to use in 12AX7 ...

Noval B9A 9-Pin tube-valve-base-Röhrensockel
ECF 802 Triode/Pentode
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Septar tubebase
=SRS4452 RFT made
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=E81L with Uf=20V
Noval B9A 9-Pin base
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Noval B9A 9-Pin tube-valve-base-Röhrensockel
ECL 81 Triode/Pentode
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Octal K8A 8-Pin tube-valve-base
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