The CV2799 is a double beam transmitting tetrode following the European pattern of a central flat cathode surrounded by a split control grids (one half per valve), a common screen grid beam forming plates and two wing shaped anodes.
The anodes are finned for good heat dissipation and the anodes are brought out to pin like top caps with stout struts for both rigid support and to aid cooling by conduction.
The heater runs at 6.3 Volts when both halves are in parallel or 12.6 Volts when in series. For 6.3 volts pins 1 & 7 are connected together with pin 5 as the other end. For 12.6 Volt operation the voltage is connected to pins 1 & 7 with pin 5 left unconnected.
In addition to use as transmitter power amplifiers the upper frequency of 600 MHz made them popular for frequency multiplication.
The pin entering the centre of the picture from the right connects to the dark beam forming plates.