[Boatanchors] Diode Brick ID?

[kmd xplornet.ca]

Hi Folks,
Among some HV stuff I pulled out of a closed AM station are a half dozen
Diode bricks. They are about 2 in x 2 in x 6 in and the only identifiers on
them are these numbers  215002 16CCA 9035 812 which makes no sense to
me.They appear to be potted so opening one up will not be possible.
I wonder if anyone can hazard a guess as to voltage and current ratings?
Thanks

73,
Keith ve3ts