The VT-86 is the American Government specification, commercially this is a 6K7 variable-μ pentode that was designed for RF and IF amplifiers in 'modern' superhet receivers with AGC control.
The Ken-Rad name and Made in USA.
The thin metal envelope is 25 mm in diameter and, excluding the IO base pins, is 62 mm tall.
References: Data-sheet & 1040. Type VT-86 was first introduced in 1936.