L30 Made by Osram for the General Electric Company Ltd. of England

Originally made in 1938, this mint tube is the actual sample supplied to the BBC research department on 30th June 1939.

The L30 was approved 19th July 1939 and given the serial number 482202.  Here are the test results;

We still have the orignal blue and gold box, which is in good condition despite its' age.