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 base shell has split open and this has been seen several times before on the smaller GT valves.
The screening cylinder obscures the main details that can only be seen at a very acute angle under a glass. There are three wire grids and the control grid wire is pinched together at the supports to leave a small hole around the cathode tube.
The pinch components. The outer screen connects to the screen around the base of the grid supports. the outer pair of supports connect to the cylindrical anode.
The wide glass tube envelope is 28 mm in diameter, and excluding the IO base pins is 74 mm tall.