The Mobile Defense Unit (MDU) was a versatile vehicle capable of several configurations used in the Galactic Civil War from around 0 ABY.
Used by the Galactic Empire, the Alliance to Restore the Republic, and the Zann Consortium, these vehicles were essentially mobile pads that were capable of being upgraded for a variety of tasks— tasks that a normal turret pad could not complete. However, a drawback to the design was that once a unit had deployed its equipment it was unable to move at all until the equipment was removed and the vehicle had packed up again.
The MDU appeared consistent in design, but sported different colors and decals between the three factions.
The Rebel Alliance could use these pads as a mobile shield generator that covered an area with the shield, a Rebel vehicle repair station that repaired vehicles in close proximity, and a rapid fire laser cannon effective against both infantry and vehicles.
The Empire could use these turrets as an EM field generator that jammed enemy missiles' guidance systems, keeping them from hitting their target, a concussion grenade mortar that could fire a volley of grenades, and an offensive sensor node that revealed a larger part of the map of the battlefield and could defend itself with an energy discharge weapon.
The Zann Consortium could use these pads as a sensor scrambler, jamming enemy missiles and hiding a limited number of units within a specific radius from enemy radar; a ysalamir cage, negating Force-related powers within a specified radius, causing them to be inactive; and a rocket pod that fired a volley of rockets that detonated on impact and could also be used as anti-aircraft weapon.