The 8608 is described as a premium quality power pentode. It was designed for wideband video power amplification.
The anode is a box on either side of the valve. The working face is about 5 mm wide and the box reaches back towards the glass by about 8 mm. The bright shapes are the beam plates and on the left can be seen the edge of the screen grid winding.
On the right the screen grid winding can be more clearly seen. The wires are thin and close spaced, much like the control grid of lower mutual conductance valves.
Looking along the grid axis reveals the geometry of the construction. Both anode sections are joined together at the top.
