The Catkin version of the VMS4 variable μ screened tetrode dates from 1934. It was designed for RF and IF amplification in broadcast superhet receivers.
The screw top cap. Looking into the valve one can see that the actual copper anode is of much smaller diameter than the outer screening can.
This M-OV valve carries the consumer Osram label.
The wide metal tube envelope is 34 mm in diameter and, excluding the B5 base pins, is 107 mm tall.
References: Data-sheet & 1005 Type VMS4 was first introduced in 1931.