The Com Guards simply paint their vehicles white for official occasions and use appropriate camouflage for combat.
Per FM: ComStar, page 17.
Highlander, Black Knight, Exterminator, Crab, Battle of Tukayyid (front cover)
Black Knight, Battle of Tukayyid (p 171)
King Crab, Battle of Tukayyid (p 178)
The insignia of the Sixth Army shows an armored knight, standing with a sword in one hand and a mace in the other. Per FM: ComStar, page 30.