The G180/2M is a voltage stabiliser tube that operates with currents through the valve of between 5 and 45 mA and maintains a voltage of 150 Volts. a(a) is a priming anode.
The two anodes are vertical rods.
The other side of the envelope has the printed CV designation for this valve.
The wide glass tube envelope is 29 mm in diameter, and excluding the B8B base pins is 62 mm tall.
References: Data-sheet. Type G180/2M was first introduced in 1958. See also1958 adverts.
