The UCL82 triode pentode was designed for single ended audio output stages in universal mains domestic equipment, normally radios. In this application the output of 3 Watts was more than adequate for most rooms but the discolouration of the glass on two UCL82 exhibits suggest that they had a hard life.
For television use, with more valves in the chain, the 300 mA version the PCL82 would have been appropriate. The standard for AC mains sets using a mains transformer would have been the ECL82.
The triode on the right sits at right angles to the pentode with the screen between. Close observation shows the pentode to actually be a beam tetrode.
The face of the pentode anode.
The thin glass tube envelope is 20 mm in diameter, and excluding the B9A base pins is 71 mm tall.
References: Data-sheet, 1040 & 1043. Type UCL82 was first introduced in 1956.