The Rebel Van is a tracked transport vehicle developed and used by the Rebel Army.
The Rebel Van was designed to give soldiers a temporal home, which is the reason why there are always a few of them inside. The Rebel Army eventually realized that this was expensive and ineffective, so the Rebel Van models were discontinued.
A larger model called the Rebel Van+ was under development. For unknown reasons, it does not appear in any of the main games. An incomplete sprite of it is seen in the series' 10th anniversary website.
Both the Rebel Van (with different colors) and Rebel Van+ (with a complete sprite) appear in Metal Slug Attack as customizable bases. All variants cost 1,000 medals each.