The VT-1 is the Type designation given to the Western Electric Type J by the American Signal Corps. It is also named as part of the WE 203 series as 203A. The American Navy called the valve CW-933.
This exhibit is a very early example. It acquired the name J Type due to the shape of the glass support.
The valve itself is a rugged triode designed for use as a detector, amplifier or local oscillator. During WWI (1914-1918) Western Electric produced around half a million valves of the VT-1 and VT-2 type.
A closer look: single twisted filament, dual ladder grids and dual anode plates.
The original box.
Thanks to Joe Gruber for sending the images.
The wide glass tube envelope is 32 mm in diameter, and including the base pins is 105 mm tall.