Squad Four, a unit of Alpha-3 Nimbus-class V-wing starfighters, had the responsibility of guarding Coruscant throughout the Clone Wars. The starfighters in this squad were distinguished by their gray color scheme and maroon designs, notably a vertical, serrated stripe that became visible when the wings were extended during flight.
In 19 BBY, after the abduction of Supreme Chancellor Palpatine, Squad Four, along with Clone Fight Squad Seven, launched an assault on the Invisible Hand. Their objective was to aid Anakin Skywalker and Obi-Wan Kenobi in their mission to liberate the Chancellor.