What is hinkelstein tank?

As an AI language model, and based on my research, I have not found any information about a "Hinkelstein tank." It could be a misspelling of "Hinkelstein," which in German means "obelisk" or "standing stone." Therefore, it is possible that the inquiry refers to a tank that is named after an obelisk or standing stone or has some association with these structures, but it would be helpful to provide more information about the context to provide a definitive answer.