The CV1111 is a high vacuum half wave rectifier. The prototype was the VI907.
This exhibit has ceramic insulator whereas other Cv1111 exhibits have mica insulators with additional ceramic inserts. SeeCV1111 for example.
The filament tension springs look to be set an angle. This is because lower down in the anode cavity is a ceramic insulated horizontal bar that forces the oxide coated filament strands to hang parallel to the anode walls.
The shape of the nickel anode pressing.
The classic envelope is 54 mm in diameter, and excluding the B4 base pins is 125 mm tall.
