The CV2020 is a miniature all glass pentode with flying leads welded to the pins and a Paxolin disc fitted. The basic valve is an EF95 / CV850.
The KB/DC identifies this valve as being made to specification K1001 or K1006, the B denotes qualification by a UK authority and the DC identifies the maker as Mullard Radio Valve Co., Whyteleafe.
The gap in the end wall of the anode allows all three wire grids to be seen.
The wire tabs attached to the base pins are a post production addition.
The thin glass tube envelope is 18 mm in diameter, and excluding the B7G base pins and flying leads is 37 mm tall.
References: Data-sheet & 1040. Type CV2020 was first introduced in 1953. See also1953 adverts.
