The BVA216 was a war time valve made available for civilian radio sets.
The BVA216 was made by Mullard and is the DW4/350 full wave rectifier. There is no minimum series resistance quoted and the maximum value of reservoir capacitor is given as 16 μF.
A front view of the anode plus codes etched into the glass.
The anodes side view. The springs at the top tension the oxide coated ribbon filaments.
The filament ribbon on the left can be seen to have an oxide coating.
The classic envelope is 45 mm in diameter, and excluding the B4 base pins is 110 mm tall.
References: 1043 & 1040. Type BVA216 was first introduced in 1936. See also1936 adverts.