The Color Corps of the Knights of Columbus are the uniformed members of the Fourth Degree. They are the ones that are most noticeable at church and public functions, parades, etc. All others are Color Guard. The Corps basically follows a Naval theme with ranks and insignia. Note that the chapeaux, which are never called hats, are similar to the old naval uniforms.
Cape colors are an indication of rank.
Vice Supreme Masters wear blue capes and chapeaux. Masters wear gold capes and chapeaux. Commanders wear purple capes and chapeaux. Other Color Corps Members wear red capes and chapeaux. Within the local assemblies, the Master more or less sets the rules.