This exhibit is a modern (as of 2014) implementation of the classic 6V6GT audio beam tetrode. JJ Electronic is based in the Slovak Republic.
Originally the 6V6 was used as a single ended audio output stage in broadcast receivers. It was an excellent design and modern useage is in push pull for lower even harmonic distortion and greater power.
The gap in the anode reveals the two wire grids and the bright beam forming plates.
A close-up of the grids through the end of the anode.
The anode box seen in the direction of electron flow. It can be seen that both g1 and g2 are wound on copper supports.
The top mica components.
The wide glass tube envelope is 32 mm in diameter and, excluding the IO base pins, is 78 mm tall.