Military markings on United States army vehicles were upgraded in August 1942 when specific new rules were adopted. New marks, from the national identification symbol downwards were ordered to be put on "all motor vehicles assigned to tactical units".
Army regulation AR-850-5 issued August 1942 ordered a plain white five pointed star, as the national symbol, it was seen in all theatres from 1943 and by 1944 was the most common national identification sign. The star point was supposed to be facing rearwards on flat surfaces, upwards on a glacis.
In armored units, the white star was often painted out or a circle around the star was added, to avoid looking like a German cross at distance. 2nd Armored painted the vehicle number on the turret side in yellow for the same reason in Normandy, with the numbers being removed by D+14.
The August 1942 regulations authorised, when camouflage and concealment outweighed recognition requirements, the national insignia could be dulled, painted over with olive drab lacklustre gasoline solvent paint, or covered.