The 11E3 is a beam tetrode with aligned grids designed for pulse operation in television line output service and similar applications. The valve can withstand a positive anode surge of 12,500 Volts.
The anode is blackened to assist radiating away the heat generated. The ceramic insulators testify to the high voltages that appear on the anode in TV service.
The anode with open slots at the ends. The anode supports are separated from the mica discs with ceramic insulators.
Looking along the grids, the screen grid passes flat across the cathode and the control grid wires can just be seen to have the same pitch and are aligned to the screen grid. the flanges in the centre of the working face provide fixing points and extra surface area for heat radiation.
The classic envelope is 54 mm in diameter and, excluding the B7 base pins, is 125 mm tall.
