The Aperture warps-in all Vaul aerospace units from vast distances almost instantly.
The Xel'Naga mastered Warp Gate technology long before the Protoss existed. When the Overmind betrayed its creators, all knowledge of the technology was thought lost save for the less advanced Stargates used by the Protoss. Because of this, the Vaul have a great advantage over all three Koprulu powers. With the ability to move intergalactic distances, the Vaul can reserve the bulk of their forces in another galaxy should their vanguard fall as the United Earth Directorate did.
Like Conduits, Apertures are used to transport flying units from secret ship yards into the Koprulu Sector. At first glance, these gateways appear as two open Warp Gates back-to-back with a crystal ring in the middle (Command & Conquer: Warp Chasm; Stargate - SG1: Ori Supergate). The crystal ring expands itself to accommodate numbers ranging from a single fighter to a small armada (Star Trek - Enterprise: Automated repair station). To prevent the same mistake done during the evacuation of Aiur, Apertures are equipped with a special energy shield that filters out ally and enemy forces upon reintegration (Stargate - Atlantis: Stargate shield). If any enemy unit tries entering an Aperture, their molecules would be lost somewhere in-between galaxies.