The CV273 is a disc seal triode based on the VX3018 but commercially known as the DET22.
Looking at the anode and grid disc. The grid proper is wound as a frame grid and fixed on the cathode side of the central grid support disc.
With the low power microscope the grid can be seen including the individual wires. Although the grid appears to be wound round the former, the active grid is one sided.
Reference: Data-sheet. Type CV273 was first introduced in 1945. See also1945 adverts.
