This beast runs at a hair raising 3000V and output 70W of SE power or 1.4KW at PP!
Max annode dissipation is 275W and the filament burns at 90W just to fire it up. Pretty useful for those cold winter nights.
The Type 4212 is obsolete & extremely expensive. The last remaining stock disappeared into Japan where they ended up in the houses of the exceedingly rich and ..believe this or not..into these guys' discos!!