[Boatanchors] tube equivalents

[dartaviation@btopenworld.com]

Good day Gentlemen,
I wonder if anyone could direct me to a site that contains the equivalent information from CV annotated tubes to the commercial type numbers please.
I seem to recall that there was a site mentioned sometime ago but unfortunately I did not make any note of the details.
I have aquired two tubes type CV 6131 and I need the details.

I am most grateful in advance for any information.

All good wishes,

Clive GW3WEQ
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