The CV3575 has the commercial equivalent of 3B26 and is described as a high vacuum clipper diode. The peak anode voltage is 15 kV and the peak anode current is 8 Amps. The total anode dissipation is 25 Watts.
The anode is supported by the top cap and has four side flanges.
The inside seen from the base. The helical structure may be the heater. When energised the cathode glow is the dim orange of a coated cathode the helical structure does not glow.
The wide glass tube envelope is 28 mm in diameter, and excluding the IO base pins is 96 mm tall.