The CV10341 (PL36) was designed as a line timebase output valve for television receivers. In 1962 it was replaced by the PL500.
The design dates to the 1950s, when sets were black and white and screen sizes of 14 - 17 inches diagonal were common. The PL36 was designed for driving the line deflection on 90° deflection angle tubes with a final EHT of 16 kV.
The maximum positive peak voltage on the anode is 7 kV and the screen dissipation is up to 5 W.
The valve is described as a pentode but the construction is as a beam tetrode. The beam plates can be seen within the anode.
Looking along the grid axis all that can be easily seen is the beam plate end.
The wide glass tube envelope is 29 mm in diameter and, excluding the IO base pins, is 91 mm tall.
References: Data-sheet & 1040. Type CV10341 was first introduced in 1956. See also1956 adverts.