The VU120 shown here has no makers mark but is clearly made by Cossor because of the distinctive hand made style. SeeSU2150A for full details.
The saddle anode is connected to the top cap and is supported on glass pillars. The cathode assembly is always at least 6 mm distant from the anode, and is a horizontal rod. The maximum reservoir capacitor is 0.25 µF, and the minimum series resistance is 10 k Ohms.
This exhibit looks to have been kept in stores for some time. The side stamp says that the base has been re-fixed and that the valve is serviceable.
The fixing of the anode to the supports and top cap. As a low power device the anode is left as bright nickel. The ridges formed in the anode sheet help it to retain its shape even though the sheet metal is flimsy. Also visible is the wire wrapped found the heater support that connects to the cathode tube.
The balloon envelope is 50 mm in diameter and, excluding the B4 base pins, is 115 mm tall.