The 19th favors gray color schemes because they make it easier to repaint their machines to look like bandits. For parade colors, they add white and light blue stripes.

Per FM:Draconis Combine, page 65.

Other references:
Charger, CM: Kurita (p 103)


Insignia:

The Galedon Regulars insignia is a gray-white katana set over a field composed of one blue and one black triangle. This insignia is always painted on a BattleMech’s upper right leg or on the fuselage of an aerospace fighter. The unit’s insignia is a grinning jack-o-lantern. Per FM: Draconis Combine, pages 59 and 65.