The CV1937 is an RF pentode. The prototype was the 6J7GT and the CV1937 is identical and both designations appear on the valve. The 6J7GT is etched on the glass and this indicates original manufacture. The CV Type is printed on the base shell.
The commercial 6J7GT. There are marks on the lower part of the glass left by the cement that once held the metal base skirt. The construction is as an all glass valve with flying leads that have been fed into the hollow pins in the plastic base and then soldered to those pins.
Looking under the outer grey screen can be seen the cylindrical anode and wire grids.
The top of the screen with the tops of the electrode supports.
The wide glass tube envelope is 28 mm in diameter, and excluding the IO base pins is 71 mm tall.