This is a Mullard EL34, despite being labelled with the Brimar logo.
Here is a front view
and a back view..
The anode is welded and has has two letter-box holes.
How we can tell it is a Mullard?
We can tell it is a Mullard if we look at the base which has a distinctive hole in the centre of the locating, centre pin.
If we look on the glass, low down, near the base and usually on the opposite
side to the label we find a number etched into the glass:
This kind of marking is found on all the Mullard made valves I've seen.
It is very hard to fake as the etching can't be scratched or rubbed off.