This valve has no Type designation visible. Cossor used paper labels with the type designation and the V9 is a manufacturing code.
A closer look at this power triode. The four inverted V's of the oxide coated filament offers eight emitting strands. The box anode is blackened to make a better radiator and the wire grid can be easily seen.
Thanks to Mark for this donation.
The classic envelope is mm in diameter, and excluding the B4 base pins is mm tall.
Updated April 27, 2013.