This exhibit is another VT from Atlantic-Pacific with unusually high levels of phosphorus gettering.
The box for this exhibit. The size is 50 mm square and 128 mm long.
Thanks to Joe Gruber for sending the images.
The balloon envelope is 44 mm in diameter and, excluding the UV base pins, is 104 mm tall.
Reference: Joe Gruber. Type VT was first introduced in 1919.
Updated August 04, 2020. shape:balloon construction:pinch type:triode age:pre.1920 base:uv pins:4 pin:1.g1 pin:2.f pin:3.f pin:4.a