Installation 04 may refer to the following:
- Installation 04 - One of the Forerunner's anti-Flood megastructures, also known as Alpha Halo.
- Installation 04 (Firefight map) - The Halo: Reach Firefight level bundled with Halo: Combat Evolved Anniversary and included in the Anniversary map pack.
- Installation 04 (music) - A soundtrack included in the Halo: Combat Evolved Anniversary Original Soundtrack.
- Battle of Installation 04 - The battle between human and Covenant forces on Installation 04.
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