The D50B is a water cooled triode made by Federal. It looks to be the same as the D50 except for taped holes to mount a coronal ring assembly. This tube appears to be a 150 KW F-134 with coaxial filament connections. The data given is for the F-134.

Length = 34.50" Diameter = 10.00" (including coronal ring)
Max voltage = 20,000
Max current = 24 amps
Fil voltage = 25
Fil current = 650 amps         GOTO INDEX