Moray space mine
From Halopedia, the Halo wiki
Moray space mines are explosives built by the United Nations Space Command for use in deep-space combat. These mines carry a high explosive payload and small chemical propellant drives that allow them to track specific targets or maintain a pre-defined coordinate location in space. Winter-class prowlers are equipped with a single, aft-mounted CBU-R68 Moray system for their secondary armaments.
They are dropped from the bays of Longsword interceptors to mine locations within space from hostile incursions. They use both proximity and remote detonators and have very high explosive payloads. This may not be a regular armament as John-117 noticed that the cryo-tube had been removed to make way for this. During the assault on Ascendant Justice, these were used to destroy the ship's Seraph fighters making way for a Longsword to land on the Covenant ship. They may also have adhesive or magnetic quality to them as they were able to be attached to a remote piloted Pelican and later deployed from it.
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