too many 88s did[:@] the circle was painted with a mix containing chemicals If specific wartime chemical agents were detected, the ring would change colors....blue or red....some debate on exact coloring in regard to certain chemicals. This was supposed to be the initial gas attack warning, but the normandy star was used only in this campaign and disconitued after it was fround that Germany was not using gas. Some variations were seen in Africa, but there are doubts that these were chemical treated...most likely units which served in Normany and later moved to Africa, still had the same markings. Vehicles marked with the Normandy star after the campaigne was over were in violation of (then) current Army Regs.