The VMP4 or VMP4K is a variable μ screened amplifier pentode for RF and IF amplification in superhet receivers. This exhibit is the Catkin version and internally is totally different to the glass replacement the VMP4G.
The seven pins fit into a Paxolin support and a composition base.
The Catkin label and Osram branding.
The top cap is fixed and not screw on.
The B7 base.
The envelope is 39 mm in diameter and, excluding the B7 base pins, is 115 mm tall.
References: Data-sheet & 1043. Type VMP4 was first introduced in 1934. See also1934 adverts.