Military police deployed within Vietnam applied distinctive markings on their helmets as was authorized by the standard army regulations covering MP insignia. Modifications were however made. Due to the requirement that the presence of military police be easily seen within the crowded avenues and roads of Vietnams cities and towns, the insignia used by the MP's in Vietnam often defied the authorized sizes and were larger than three inches in width.

Camouflaged helmet covers were not usually worn by military police except where the unit was considered to be imminently employed in combat. In the case of the 3rd platoon these would only be worn on Gate guard or when guarding the Brigade Tactical Operations Center (BTOC). The 23 MP's stationed at Chu Lai HQ of the Americal would wear these as their normal duty uniform, where the 3rd platoon would wear "steel pots"

MP helmets or helmet liners were painted gloss black and decorated with large "MP" letters in white on the front. A painted band then extended around the helmet. This band may have been white, red, red and blue, or red and white depending on the circumstances of the unit assignment. The left side of the helmet was usually used for the unit designation with the right side being used by unit insignia the numeral "23".