EZ81 NEW UNUSED BY LA RADIOTECHNIQUE RFT OR EI
Now these are a bit of an enigma because I don't know who has made them. They date from the 1970s and are from a small scale manufacturer of radiograms who went on to design and produce Amstrad's first transistor amplifier.
The envelope carries white print and a coding FJ - a La Radiotechnique factory code. The B9A glass button carries a stamped number-letter code as per Siemens and RFT devices, however, the black anode and anode construction does not resemble Siemens or RFT devices. We think these may be Yugoslav EI devices. Whatever they are and whoever made them they are wonderful strong devices available at a very keen price for vintage high performance rectifiers - once they've gone thats it!