The Imperial Castellans primarily wear cerulean blue Power Armour, which includes the power pack, helm, shoulder plates, torso and groin. The shoulder plate trim, arms and legs are bone. The black squad specialty symbol -- Tactical, Assault, Devastator or Veteran -- is displayed on the right shoulder plate. A white Gothic numeral centred on the squad specialty symbol indicates squad number. The colour of the Aquila or Imperialis on the chest plate indicates company designation in accordance with the Codex Astartes -- i.e. White (1st Company), Yellow (2nd Company), Red (3rd Company), etc.
The Imperial Castellans' Chapter badge is an ebon silhouette of an arm wearing ancient plate armour holding a sword aloft, on a field of cerulean blue.
- Adeptus Astartes: Successor Chapters (Limited Release Booklet)
- Insignium Astartes, pg. 59