The Medium Fusion Destructive Device, or MFDD, commonly referred to in the UNSC as the "Mike Foxtrot Delta Delta" is a tactical nuclear weapon with a yield of 63 terajoules (approximately 15 kilotons TNT equivalent), used by the United Nations Space Command. It was manufactured by Misriah Armories. An MFDD was used by Noble Team to destroy a CCS-class battlecruiser during the Battle of Fumirole during the Human-Covenant war.