From Halopedia, the Halo wiki
ADP-class escort is a class of escort ship that was in service with the now-defunct fleet of the Covenant during the Human-Covenant War. The vessel was more common in the Covenant's core regions rather than in crusading fleets.
Considered to be a ship for protectors and shepherds, ADP-class escorts were rare and valued antiquities within the Covenant fleet, having originated from an Age of Conversion in which the Covenant spread knowledge of their Great Journey to a new species. The Age of Conversion was also an age of conflict, leading to ADP-class escorts being commissioned to provide protection to Covenant merchants and pilgrims from pirates that lurked throughout the empire's space and the greed of zealous ministers seeking to expand their influence and wealth.
Halo: Fleet Battles
Covenant ADP Escort Tri-Formation
This element includes three ADP-class escorts.
List of appearances