This is a list of VK-designated tanks made by Germany from 1930s until 1945.
from Versuchs Kraftfahrzeug meaning "research/experimental vehicle,"[citation needed] was used in the names of some German experimental or prototype tanks produced before and during World War II.
VK term was also referred to as Vollketten' ( "fully tracked").
31) with VK meaning Volketten (Vs. Kfz.
meaning Versuchskampffahrzeug), and number "31" denoting the year of development.